Prediction Markets 2028 Democratic Presidential Nominee

2028 Democratic Presidential Nominee Odds

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Updated 30 minutes ago · 3:44 PM PDT

Gavin Newsom leads the 2028 Democratic nomination at 18.8%, holding frontrunner status off a February book tour that doubled as a campaign prelude and a Guardian quote about "stepping into that void" if no one else brings the fire. Alexandria Ocasio-Cortez has a 14.3% chance, still weighing a presidential run against a 2028 Senate primary challenge to Chuck Schumer. Jon Ossoff rounds out the top three at 14.2% after a recent rally in Augusta where he tore into the "Mar-a-Lago Mafia" over the Iran war, affordability, and corruption. DeFi Rate's custom odds tracker blends live pricing from Kalshi, Polymarket, and Forecastex into a single consensus probability, refreshed hourly.

Largest Spread

2.53%

Rahm Emanuel → View arbs

Current Favorite

18.8%

Gavin Newsom 16.6%

24H Volume (Share)

$731.3K

Momentum Leader

+10.7%

Jon Ossoff YTD change

Current Odds Snapshot

Current probabilities across platforms with liquidity indicators

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Gavin Newsom

Vol $28.0K Spread 11.5%

Agg 18.8%

↓ -16.6%

California Governor

F 29.0%

P 19.5%

K 17.5%

ForecastEx 29.0%

Vol $0 29¢

Polymarket 19.5%

Vol $18.2K 19.4–19.5¢

Kalshi 17.5%

Vol $9.8K 17–18¢

AOC

Alexandria Ocasio-Cortez

Vol $15.1K Spread 2.9%

Agg 14.3%

↑ +2.4%

NY Representative

F 17.0%

K 14.5%

P 14.1%

Jon Ossoff

Vol $58.0K Spread 0.4%

Agg 14.2%

↑ +10.7%

K 14.5%

P 14.1%

Kamala Harris

Vol $80.4K Spread 1.2%

Agg 9.5%

↑ +5.5%

K 9.9%

F 9.0%

P 8.8%

Pete Buttigieg

Vol $23.9K Spread 8.5%

Agg 5.6%

↑ +1.1%

F 14.0%

K 6.1%

P 5.6%

Josh Shapiro

Vol $46.8K Spread 5.5%

Agg 4.6%

↑ +0.4%

F 10.0%

P 4.9%

K 4.5%

Rahm Emanuel

Vol $1.3K Spread 2.7%

Agg 4.0%

↑ +2.0%

K 5.1%

P 2.4%

Andy Beshear

Vol $137.4K Spread 6.6%

Agg 3.4%

↑ +0.8%

F 9.0%

K 3.5%

P 2.5%

Mark Kelly

Vol $17.5K Spread 0.8%

Agg 2.5%

↑ +0.7%

K 3.1%

P 2.3%

Ro Khanna

Vol $3.8K Spread 0.2%

Agg 2.3%

↑ +1.1%

K 2.4%

P 2.2%

James Talarico

Vol $131 Spread —

Agg 1.6%

↑ +1.0%

K 1.6%

Kalshi 1.6%

Vol $131 1.5–1.6¢

Jon Stewart

Vol $1.6K Spread 1.2%

Agg 1.4%

↑ +0.6%

Comedian

P 2.3%

K 1.1%

Wes Moore

Vol $100.7K Spread 3.7%

Agg 1.4%

↓ -1.1%

F 5.0%

K 2.7%

P 1.4%

Dwayne Johnson

Vol $3.7K Spread 1.0%

Agg 1.2%

↓ -0.1%

P 1.2%

K 0.2%

Gretchen Whitmer

Vol $2.0K Spread 7.0%

Agg 1.1%

↓ -0.7%

F 8.0%

P 1.6%

K 1.1%

JBP

J.B. Pritzker

Vol $84.5K Spread 2.9%

Agg 1.1%

↓ -1.0%

F 4.0%

K 2.7%

P 1.1%

Michelle Obama

Vol $7.6K Spread 0.3%

Agg 1.0%

— +0.0%

K 1.3%

P 1.0%

Chelsea Clinton

Vol $8.5K Spread —

Agg 0.9%

↑ +0.3%

P 0.9%

Polymarket 0.9%

Vol $8.5K 0.8–0.9¢

Jasmine Crockett

Vol $6.9K Spread —

Agg 0.7%

↑ +0.1%

P 0.7%

Polymarket 0.7%

Vol $6.9K 0.6–0.7¢

Roy Cooper

Vol $422 Spread 0.4%

Agg 0.7%

— +0.0%

P 0.7%

K 0.3%

Bernie Sanders

Vol $6.2K Spread 0.1%

Agg 0.6%

↑ +0.2%

P 0.7%

K 0.5%

SAS

Stephen A. Smith

Vol $2.9K Spread 0.2%

Agg 0.6%

↓ -0.1%

P 0.7%

K 0.4%

Mark Cuban

Vol $209 Spread 0.2%

Agg 0.6%

↓ -0.1%

K 0.8%

P 0.6%

Hunter Biden

Vol $57.2K Spread 0.4%

Agg 0.6%

— +0.0%

K 0.9%

P 0.5%

Chris Murphy

Vol $920 Spread 0.1%

Agg 0.5%

↓ -0.1%

K 0.7%

P 0.5%

Cory Booker

Vol $10.6K Spread 0.0%

Agg 0.5%

↓ -0.1%

K 0.5%

P 0.5%

Elissa Slotkin

Vol $12 Spread —

Agg 0.5%

— +0.0%

K 0.5%

Kalshi 0.5%

Vol $12 0.5–0.6¢

Raphael Warnock

Vol $1.8K Spread 0.0%

Agg 0.5%

— +0.0%

K 0.5%

P 0.5%

Oprah Winfrey

Vol $1.8K Spread —

Agg 0.4%

— +0.0%

P 0.4%

Polymarket 0.4%

Vol $1.8K 0.4–0.5¢

Ruben Gallego

Vol $586 Spread 0.1%

Agg 0.4%

↓ -0.7%

K 0.5%

P 0.4%

Lebron James

Vol $846 Spread 0.4%

Agg 0.4%

↓ -0.4%

P 0.4%

K 0.1%

Zohran Mamdani

Vol $1.1K Spread 0.2%

Agg 0.4%

↓ -0.1%

NYC Mayor

P 0.4%

K 0.3%

Barack Obama

Vol $278 Spread 0.0%

Agg 0.4%

↓ -0.3%

K 0.4%

P 0.4%

BOR

Beto O’Rourke

Vol $1.4K Spread —

Agg 0.4%

↓ -0.5%

P 0.4%

Polymarket 0.4%

Vol $1.4K 0.3–0.4¢

George Clooney

Vol $1.3K Spread —

Agg 0.4%

↓ -0.2%

P 0.4%

Polymarket 0.4%

Vol $1.3K 0.3–0.4¢

Gina Raimondo

Vol $2.3K Spread 0.2%

Agg 0.4%

↓ -0.1%

P 0.4%

K 0.2%

John Fetterman

Vol $3.6K Spread 0.2%

Agg 0.4%

↓ -0.9%

P 0.4%

K 0.2%

Phil Murphy

Vol $1.8K Spread 0.3%

Agg 0.4%

↓ -0.2%

P 0.4%

K 0.1%

Hilary Clinton

Vol $1.7K Spread 0.2%

Agg 0.3%

↓ -0.2%

P 0.4%

K 0.2%

Liz Cheney

Vol $301 Spread 0.3%

Agg 0.3%

↓ -0.3%

P 0.3%

K 0.1%

Andrew Yang

Vol $688 Spread —

Agg 0.3%

↓ -0.3%

P 0.3%

Polymarket 0.3%

Vol $688 0.2–0.3¢

Jamie Dimon

Vol $28 Spread —

Agg 0.3%

↓ -0.3%

K 0.3%

Kalshi 0.3%

Vol $28 0.2–0.3¢

Jared Polis

Vol $1.6K Spread 0.1%

Agg 0.3%

↓ -0.7%

P 0.3%

K 0.2%

Kim Kardashian

Vol $1.5K Spread —

Agg 0.3%

↓ -0.4%

P 0.3%

Polymarket 0.3%

Vol $1.5K 0.2–0.3¢

MrBeast

Vol $1.2K Spread —

Agg 0.3%

↓ -0.3%

P 0.3%

Polymarket 0.3%

Vol $1.2K 0.2–0.3¢

Tim Walz

Vol $1.4K Spread 0.1%

Agg 0.2%

↓ -0.3%

P 0.3%

K 0.2%

Outcome	Aggregated	Spread	Volume	Kalshi	Polymarket	ForecastEx
GN Gavin Newsom California Governor	18.8% ↓ -16.6%	11.5%	$28.0K	Kalshi 17.5% 17–18¢ Vol $9.8K	Polymarket 19.5% 19.4–19.5¢ Vol $18.2K	ForecastEx 29.0% 29¢ Vol $0
AOC Alexandria Ocasio-Cortez NY Representative	14.3% ↑ +2.4%	2.9%	$15.1K	Kalshi 14.5% 14–15¢ Vol $8.6K	Polymarket 14.1% 14–14.1¢ Vol $6.5K	ForecastEx 17.0% 17¢ Vol $0
JO Jon Ossoff	14.2% ↑ +10.7%	0.4%	$58.0K	Kalshi 14.5% 14–15¢ Vol $14.2K	Polymarket 14.1% 14–14.1¢ Vol $43.8K	ForecastEx — —
KH Kamala Harris	9.5% ↑ +5.5%	1.2%	$80.4K	Kalshi 9.9% 9.8–10¢ Vol $49.0K	Polymarket 8.8% 8.7–8.8¢ Vol $31.5K	ForecastEx 9.0% 9¢ Vol $0
PB Pete Buttigieg	5.6% ↑ +1.1%	8.5%	$23.9K	Kalshi 6.1% 5.9–6.2¢ Vol $1.7K	Polymarket 5.6% 5.4–5.7¢ Vol $22.2K	ForecastEx 14.0% 14¢ Vol $0
JS Josh Shapiro	4.6% ↑ +0.4%	5.5%	$46.8K	Kalshi 4.5% 4.4–4.6¢ Vol $31.1K	Polymarket 4.9% 4.8–4.9¢ Vol $15.6K	ForecastEx 10.0% 10¢ Vol $0
RE Rahm Emanuel	4.0% ↑ +2.0%	2.7%	$1.3K	Kalshi 5.1% 5–5.1¢ Vol $801	Polymarket 2.4% 2.3–2.4¢ Vol $502	ForecastEx — —
AB Andy Beshear	3.4% ↑ +0.8%	6.6%	$137.4K	Kalshi 3.5% 3.4–3.5¢ Vol $135.9K	Polymarket 2.5% 2.4–2.5¢ Vol $1.5K	ForecastEx 9.0% 9¢ Vol $0
MK Mark Kelly	2.5% ↑ +0.7%	0.8%	$17.5K	Kalshi 3.1% 3–3.1¢ Vol $4.6K	Polymarket 2.3% 2.2–2.3¢ Vol $12.8K	ForecastEx — —
RK Ro Khanna	2.3% ↑ +1.1%	0.2%	$3.8K	Kalshi 2.4% 2.3–2.4¢ Vol $3.2K	Polymarket 2.2% 2.1–2.2¢ Vol $646	ForecastEx — —
JT James Talarico	1.6% ↑ +1.0%	—	$131	Kalshi 1.6% 1.5–1.6¢ Vol $131	Polymarket — —	ForecastEx — —
JS Jon Stewart Comedian	1.4% ↑ +0.6%	1.2%	$1.6K	Kalshi 1.1% 1–1.1¢ Vol $1.1K	Polymarket 2.3% 2.2–2.3¢ Vol $484	ForecastEx — —
WM Wes Moore	1.4% ↓ -1.1%	3.7%	$100.7K	Kalshi 2.7% 2.6–2.7¢ Vol $1.0K	Polymarket 1.4% 1.3–1.4¢ Vol $99.7K	ForecastEx 5.0% 5¢ Vol $0
DJ Dwayne Johnson	1.2% ↓ -0.1%	1.0%	$3.7K	Kalshi 0.2% 0.1–0.2¢ Vol $0	Polymarket 1.2% 1.1–1.2¢ Vol $3.7K	ForecastEx — —
GW Gretchen Whitmer	1.1% ↓ -0.7%	7.0%	$2.0K	Kalshi 1.1% 1–1.1¢ Vol $1.6K	Polymarket 1.6% 1.5–1.6¢ Vol $372	ForecastEx 8.0% 8¢ Vol $0
JBP J.B. Pritzker	1.1% ↓ -1.0%	2.9%	$84.5K	Kalshi 2.7% 2.6–2.7¢ Vol $2.2K	Polymarket 1.1% 1–1.1¢ Vol $82.3K	ForecastEx 4.0% 4¢ Vol $0
MO Michelle Obama	1.0% — +0.0%	0.3%	$7.6K	Kalshi 1.3% 1.2–1.3¢ Vol $198	Polymarket 1.0% 0.9–1¢ Vol $7.4K	ForecastEx — —
CC Chelsea Clinton	0.9% ↑ +0.3%	—	$8.5K	Kalshi — —	Polymarket 0.9% 0.8–0.9¢ Vol $8.5K	ForecastEx — —
JC Jasmine Crockett	0.7% ↑ +0.1%	—	$6.9K	Kalshi — —	Polymarket 0.7% 0.6–0.7¢ Vol $6.9K	ForecastEx — —
RC Roy Cooper	0.7% — +0.0%	0.4%	$422	Kalshi 0.3% 0.2–0.3¢ Vol $0	Polymarket 0.7% 0.6–0.7¢ Vol $422	ForecastEx — —
BS Bernie Sanders	0.6% ↑ +0.2%	0.1%	$6.2K	Kalshi 0.5% 0.5–0.6¢ Vol $11	Polymarket 0.7% 0.6–0.7¢ Vol $6.1K	ForecastEx — —
SAS Stephen A. Smith	0.6% ↓ -0.1%	0.2%	$2.9K	Kalshi 0.4% 0.4–0.5¢ Vol $24	Polymarket 0.7% 0.6–0.7¢ Vol $2.8K	ForecastEx — —
MC Mark Cuban	0.6% ↓ -0.1%	0.2%	$209	Kalshi 0.8% 0.7–0.9¢ Vol $0	Polymarket 0.6% 0.5–0.7¢ Vol $209	ForecastEx — —
HB Hunter Biden	0.6% — +0.0%	0.4%	$57.2K	Kalshi 0.9% 0.8–1¢ Vol $1.1K	Polymarket 0.5% 0.5–0.6¢ Vol $56.1K	ForecastEx — —
CM Chris Murphy	0.5% ↓ -0.1%	0.1%	$920	Kalshi 0.7% 0.6–0.7¢ Vol $0	Polymarket 0.5% 0.5–0.6¢ Vol $920	ForecastEx — —
CB Cory Booker	0.5% ↓ -0.1%	0.0%	$10.6K	Kalshi 0.5% 0.5–0.6¢ Vol $3	Polymarket 0.5% 0.5–0.6¢ Vol $10.6K	ForecastEx — —
ES Elissa Slotkin	0.5% — +0.0%	—	$12	Kalshi 0.5% 0.5–0.6¢ Vol $12	Polymarket — —	ForecastEx — —
RW Raphael Warnock	0.5% — +0.0%	0.0%	$1.8K	Kalshi 0.5% 0.5–0.6¢ Vol $47	Polymarket 0.5% 0.5–0.6¢ Vol $1.8K	ForecastEx — —
OW Oprah Winfrey	0.4% — +0.0%	—	$1.8K	Kalshi — —	Polymarket 0.4% 0.4–0.5¢ Vol $1.8K	ForecastEx — —
RG Ruben Gallego	0.4% ↓ -0.7%	0.1%	$586	Kalshi 0.5% 0.5–0.6¢ Vol $0	Polymarket 0.4% 0.4–0.5¢ Vol $586	ForecastEx — —
LJ Lebron James	0.4% ↓ -0.4%	0.4%	$846	Kalshi 0.1% 0–0.1¢ Vol $1	Polymarket 0.4% 0.4–0.5¢ Vol $845	ForecastEx — —
ZM Zohran Mamdani NYC Mayor	0.4% ↓ -0.1%	0.2%	$1.1K	Kalshi 0.3% 0.2–0.3¢ Vol $4	Polymarket 0.4% 0.4–0.5¢ Vol $1.1K	ForecastEx — —
BO Barack Obama	0.4% ↓ -0.3%	0.0%	$278	Kalshi 0.4% 0.3–0.4¢ Vol $9	Polymarket 0.4% 0.3–0.4¢ Vol $269	ForecastEx — —
BOR Beto O’Rourke	0.4% ↓ -0.5%	—	$1.4K	Kalshi — —	Polymarket 0.4% 0.3–0.4¢ Vol $1.4K	ForecastEx — —
GC George Clooney	0.4% ↓ -0.2%	—	$1.3K	Kalshi — —	Polymarket 0.4% 0.3–0.4¢ Vol $1.3K	ForecastEx — —
GR Gina Raimondo	0.4% ↓ -0.1%	0.2%	$2.3K	Kalshi 0.2% 0.1–0.2¢ Vol $0	Polymarket 0.4% 0.3–0.4¢ Vol $2.3K	ForecastEx — —
JF John Fetterman	0.4% ↓ -0.9%	0.2%	$3.6K	Kalshi 0.2% 0.1–0.2¢ Vol $0	Polymarket 0.4% 0.3–0.4¢ Vol $3.6K	ForecastEx — —
PM Phil Murphy	0.4% ↓ -0.2%	0.3%	$1.8K	Kalshi 0.1% 0–0.1¢ Vol $0	Polymarket 0.4% 0.3–0.4¢ Vol $1.8K	ForecastEx — —
HC Hilary Clinton	0.3% ↓ -0.2%	0.2%	$1.7K	Kalshi 0.2% 0.1–0.2¢ Vol $1	Polymarket 0.4% 0.3–0.4¢ Vol $1.7K	ForecastEx — —
LC Liz Cheney	0.3% ↓ -0.3%	0.3%	$301	Kalshi 0.1% 0–0.1¢ Vol $1	Polymarket 0.3% 0.2–0.4¢ Vol $299	ForecastEx — —
AY Andrew Yang	0.3% ↓ -0.3%	—	$688	Kalshi — —	Polymarket 0.3% 0.2–0.3¢ Vol $688	ForecastEx — —
JD Jamie Dimon	0.3% ↓ -0.3%	—	$28	Kalshi 0.3% 0.2–0.3¢ Vol $28	Polymarket — —	ForecastEx — —
JP Jared Polis	0.3% ↓ -0.7%	0.1%	$1.6K	Kalshi 0.2% 0.1–0.2¢ Vol $0	Polymarket 0.3% 0.2–0.3¢ Vol $1.6K	ForecastEx — —
KK Kim Kardashian	0.3% ↓ -0.4%	—	$1.5K	Kalshi — —	Polymarket 0.3% 0.2–0.3¢ Vol $1.5K	ForecastEx — —
MR MrBeast	0.3% ↓ -0.3%	—	$1.2K	Kalshi — —	Polymarket 0.3% 0.2–0.3¢ Vol $1.2K	ForecastEx — —
TW Tim Walz	0.2% ↓ -0.3%	0.1%	$1.4K	Kalshi 0.2% 0.1–0.2¢ Vol $5	Polymarket 0.3% 0.2–0.3¢ Vol $1.4K	ForecastEx — —

Arbitrage Scanner

Current cross-venue opportunities with fee calculations

Minimum Spread 1.5%

Include fees

Show only actionable

Pairs (Venue-to-Venue)

Outcome	Venue Pair	Leg A (Buy)	Leg B (Sell)	Gross Spread	After Fees	Actionable	Trade Now
RE Rahm Emanuel	Polymarket → Kalshi	Buy @ P 2.4¢	Sell @ K 5¢	+2.60%	+2.53%	Yes	P ↗︎ K ↗︎
JBP J.B. Pritzker	Polymarket → Kalshi	Buy @ P 1.1¢	Sell @ K 2.6¢	+1.50%	+1.43%	No	P ↗︎ K ↗︎
GN Gavin Newsom California Governor	Kalshi → Polymarket	Buy @ K 18¢	Sell @ P 19.4¢	+1.40%	+1.22%	No	K ↗︎ P ↗︎
WM Wes Moore	Polymarket → Kalshi	Buy @ P 1.4¢	Sell @ K 2.6¢	+1.20%	+1.13%	No	P ↗︎ K ↗︎
JS Jon Stewart Comedian	Kalshi → Polymarket	Buy @ K 1.1¢	Sell @ P 2.2¢	+1.10%	+1.03%	No	K ↗︎ P ↗︎
KH Kamala Harris	Polymarket → Kalshi	Buy @ P 8.8¢	Sell @ K 9.8¢	+1.00%	+0.90%	No	P ↗︎ K ↗︎
AB Andy Beshear	Polymarket → Kalshi	Buy @ P 2.5¢	Sell @ K 3.4¢	+0.90%	+0.83%	No	P ↗︎ K ↗︎
DJ Dwayne Johnson	Kalshi → Polymarket	Buy @ K 0.2¢	Sell @ P 1.1¢	+0.90%	+0.83%	No	K ↗︎ P ↗︎
MK Mark Kelly	Polymarket → Kalshi	Buy @ P 2.3¢	Sell @ K 3¢	+0.70%	+0.63%	No	P ↗︎ K ↗︎
GW Gretchen Whitmer	Kalshi → Polymarket	Buy @ K 1.1¢	Sell @ P 1.5¢	+0.40%	+0.33%	No	K ↗︎ P ↗︎
RC Roy Cooper	Kalshi → Polymarket	Buy @ K 0.3¢	Sell @ P 0.6¢	+0.30%	+0.23%	No	K ↗︎ P ↗︎
LJ Lebron James	Kalshi → Polymarket	Buy @ K 0.1¢	Sell @ P 0.4¢	+0.30%	+0.23%	No	K ↗︎ P ↗︎
JS Josh Shapiro	Kalshi → Polymarket	Buy @ K 4.6¢	Sell @ P 4.8¢	+0.20%	+0.13%	No	K ↗︎ P ↗︎
MO Michelle Obama	Polymarket → Kalshi	Buy @ P 1¢	Sell @ K 1.2¢	+0.20%	+0.13%	No	P ↗︎ K ↗︎
HB Hunter Biden	Polymarket → Kalshi	Buy @ P 0.6¢	Sell @ K 0.8¢	+0.20%	+0.13%	No	P ↗︎ K ↗︎
PM Phil Murphy	Kalshi → Polymarket	Buy @ K 0.1¢	Sell @ P 0.3¢	+0.20%	+0.13%	No	K ↗︎ P ↗︎
PB Pete Buttigieg	Polymarket → Kalshi	Buy @ P 5.7¢	Sell @ K 5.9¢	+0.20%	+0.13%	No	P ↗︎ K ↗︎
RK Ro Khanna	Polymarket → Kalshi	Buy @ P 2.2¢	Sell @ K 2.3¢	+0.10%	+0.03%	No	P ↗︎ K ↗︎
SAS Stephen A. Smith	Kalshi → Polymarket	Buy @ K 0.5¢	Sell @ P 0.6¢	+0.10%	+0.03%	No	K ↗︎ P ↗︎
ZM Zohran Mamdani NYC Mayor	Kalshi → Polymarket	Buy @ K 0.3¢	Sell @ P 0.4¢	+0.10%	+0.03%	No	K ↗︎ P ↗︎
GR Gina Raimondo	Kalshi → Polymarket	Buy @ K 0.2¢	Sell @ P 0.3¢	+0.10%	+0.03%	No	K ↗︎ P ↗︎
JF John Fetterman	Kalshi → Polymarket	Buy @ K 0.2¢	Sell @ P 0.3¢	+0.10%	+0.03%	No	K ↗︎ P ↗︎
HC Hilary Clinton	Kalshi → Polymarket	Buy @ K 0.2¢	Sell @ P 0.3¢	+0.10%	+0.03%	No	K ↗︎ P ↗︎
LC Liz Cheney	Kalshi → Polymarket	Buy @ K 0.1¢	Sell @ P 0.2¢	+0.10%	+0.03%	No	K ↗︎ P ↗︎
BS Bernie Sanders	Kalshi → Polymarket	Buy @ K 0.6¢	Sell @ P 0.6¢	+0.00%	-0.07%	No	K ↗︎ P ↗︎
MC Mark Cuban	Polymarket → Kalshi	Buy @ P 0.7¢	Sell @ K 0.7¢	+0.00%	-0.07%	No	P ↗︎ K ↗︎
CM Chris Murphy	Polymarket → Kalshi	Buy @ P 0.6¢	Sell @ K 0.6¢	+0.00%	-0.07%	No	P ↗︎ K ↗︎
RG Ruben Gallego	Polymarket → Kalshi	Buy @ P 0.5¢	Sell @ K 0.5¢	+0.00%	-0.07%	No	P ↗︎ K ↗︎
JP Jared Polis	Kalshi → Polymarket	Buy @ K 0.2¢	Sell @ P 0.2¢	+0.00%	-0.07%	No	K ↗︎ P ↗︎
TW Tim Walz	Kalshi → Polymarket	Buy @ K 0.2¢	Sell @ P 0.2¢	+0.00%	-0.07%	No	K ↗︎ P ↗︎
CB Cory Booker	Kalshi → Polymarket	Buy @ K 0.6¢	Sell @ P 0.5¢	-0.10%	-0.17%	No	K ↗︎ P ↗︎
RW Raphael Warnock	Kalshi → Polymarket	Buy @ K 0.6¢	Sell @ P 0.5¢	-0.10%	-0.17%	No	K ↗︎ P ↗︎
BO Barack Obama	Kalshi → Polymarket	Buy @ K 0.4¢	Sell @ P 0.3¢	-0.10%	-0.17%	No	K ↗︎ P ↗︎
AOC Alexandria Ocasio-Cortez NY Representative	Polymarket → Kalshi	Buy @ P 14.1¢	Sell @ K 14¢	-0.10%	-0.24%	No	P ↗︎ K ↗︎
JO Jon Ossoff	Polymarket → Kalshi	Buy @ P 14.1¢	Sell @ K 14¢	-0.10%	-0.24%	No	P ↗︎ K ↗︎

Outcome Diff

Outcome A	Outcome B	Venue	A Odds	B Odds	Diff	Strategy	Trade Now
GN Gavin Newsom	MK Mark Kelly	Polymarket	A 19.5%	B 2.3%	+17.20%	Buy spread	P ↗︎
GN Gavin Newsom	JS Jon Stewart	Polymarket	A 19.5%	B 2.3%	+17.20%	Buy spread	P ↗︎
GN Gavin Newsom	RE Rahm Emanuel	Polymarket	A 19.5%	B 2.4%	+17.10%	Buy spread	P ↗︎
GN Gavin Newsom	AB Andy Beshear	Polymarket	A 19.5%	B 2.5%	+17.00%	Buy spread	P ↗︎
GN Gavin Newsom	WM Wes Moore	Kalshi	A 17.5%	B 2.7%	+14.85%	Buy spread	K ↗︎
GN Gavin Newsom	JS Josh Shapiro	Polymarket	A 19.5%	B 4.9%	+14.60%	Buy spread	P ↗︎
GN Gavin Newsom	MK Mark Kelly	Kalshi	A 17.5%	B 3.1%	+14.45%	Buy spread	K ↗︎
GN Gavin Newsom	AB Andy Beshear	Kalshi	A 17.5%	B 3.5%	+14.05%	Buy spread	K ↗︎
GN Gavin Newsom	PB Pete Buttigieg	Polymarket	A 19.5%	B 5.6%	+13.90%	Buy spread	P ↗︎
GN Gavin Newsom	JS Josh Shapiro	Kalshi	A 17.5%	B 4.5%	+13.00%	Buy spread	K ↗︎
GN Gavin Newsom	RE Rahm Emanuel	Kalshi	A 17.5%	B 5.1%	+12.45%	Buy spread	K ↗︎
AOC Alexandria Ocasio-Cortez	WM Wes Moore	Kalshi	A 14.5%	B 2.7%	+11.85%	Buy spread	K ↗︎
JO Jon Ossoff	WM Wes Moore	Kalshi	A 14.5%	B 2.7%	+11.85%	Buy spread	K ↗︎
AOC Alexandria Ocasio-Cortez	MK Mark Kelly	Polymarket	A 14.1%	B 2.3%	+11.80%	Buy spread	P ↗︎
AOC Alexandria Ocasio-Cortez	JS Jon Stewart	Polymarket	A 14.1%	B 2.3%	+11.80%	Buy spread	P ↗︎
JO Jon Ossoff	MK Mark Kelly	Polymarket	A 14.1%	B 2.3%	+11.80%	Buy spread	P ↗︎
JO Jon Ossoff	JS Jon Stewart	Polymarket	A 14.1%	B 2.3%	+11.80%	Buy spread	P ↗︎
AOC Alexandria Ocasio-Cortez	RE Rahm Emanuel	Polymarket	A 14.1%	B 2.4%	+11.70%	Buy spread	P ↗︎
JO Jon Ossoff	RE Rahm Emanuel	Polymarket	A 14.1%	B 2.4%	+11.70%	Buy spread	P ↗︎
AOC Alexandria Ocasio-Cortez	AB Andy Beshear	Polymarket	A 14.1%	B 2.5%	+11.60%	Buy spread	P ↗︎
JO Jon Ossoff	AB Andy Beshear	Polymarket	A 14.1%	B 2.5%	+11.60%	Buy spread	P ↗︎
GN Gavin Newsom	PB Pete Buttigieg	Kalshi	A 17.5%	B 6.1%	+11.45%	Buy spread	K ↗︎
AOC Alexandria Ocasio-Cortez	MK Mark Kelly	Kalshi	A 14.5%	B 3.1%	+11.45%	Buy spread	K ↗︎
JO Jon Ossoff	MK Mark Kelly	Kalshi	A 14.5%	B 3.1%	+11.45%	Buy spread	K ↗︎
AOC Alexandria Ocasio-Cortez	AB Andy Beshear	Kalshi	A 14.5%	B 3.5%	+11.05%	Buy spread	K ↗︎
JO Jon Ossoff	AB Andy Beshear	Kalshi	A 14.5%	B 3.5%	+11.05%	Buy spread	K ↗︎
GN Gavin Newsom	KH Kamala Harris	Polymarket	A 19.5%	B 8.8%	+10.70%	Buy spread	P ↗︎
AOC Alexandria Ocasio-Cortez	JS Josh Shapiro	Kalshi	A 14.5%	B 4.5%	+10.00%	Buy spread	K ↗︎
JO Jon Ossoff	JS Josh Shapiro	Kalshi	A 14.5%	B 4.5%	+10.00%	Buy spread	K ↗︎
AOC Alexandria Ocasio-Cortez	RE Rahm Emanuel	Kalshi	A 14.5%	B 5.1%	+9.45%	Buy spread	K ↗︎

Kalshi Trading Fee 1% (min $0.07, max $1.75) per side

Polymarket Trading Fee 0% (gas only)

Gemini Trading Fee 0.40% per side

Polymarket US Trading Fee 0% (gas only)

After-fee spreads apply the configured taker-fee model per side. Depth/slippage is not modeled in this scanner.

Methodology & Data Mapping

How we aggregate, normalize, and map cross-platform data

Aggregation Method

Default: Volume-Weighted Average Price (VWAP)

Weights each mapped market by its reported 24H USD volume at snapshot time. If volume is unavailable, we fall back to a simple average for that snapshot.

Use the VWAP/Simple toggle above the chart to switch aggregation views.

Data Sources & Cadence

Kalshi: Official API (best bid/ask + last + 24H volume/liquidity when available).

Polymarket: Market data via their API (token prices + best bid/ask + 24H volume/liquidity when available).

ForecastEx: FEX API (price from latest_prices; 24H USD volume estimated from trades as sum(quantity * yes_price); no bid/ask).

Event data is updated hourly. Older history is downsampled.

Outcome Mapping

Each event links one or more markets per provider. We normalize labels, map provider outcomes into a shared outcome list, and merge mapped markets where appropriate.

Spread & Liquidity

Cross-venue spread: Max–min difference across available venue probabilities for the same outcome.

Liquidity: Relative per-venue indicators based on provider liquidity fields (no depth/slippage modeling).

Arbitrage: Computed from best bid/ask when available (otherwise mid); after-fee spread applies the configured fee model only.

Prediction Markets 2028 Democratic Presidential Nominee

2028 Democratic Presidential Nominee Odds

Probability Over Time

Current Odds Snapshot

Arbitrage Scanner

Pairs (Venue-to-Venue)

Outcome Diff

Methodology & Data Mapping