US Presidential 2028 Odds at Prediction Markets

LIVE

Updated 16 minutes ago · 4:59 AM PDT

Prediction markets expect JD Vance to win the 2028 Presidential Election, with his victory sitting at 77.0% probability (-335). A Ted Cruz win stands at 69.0% (-223), while deeper field candidates remain unlikely at sub-10% probability. Our 2028 US election tracker aggregates live odds from 4 prediction markets. The total volume in the last 24 hours stands at $4.1M, with $1.8M at Kalshi and $2.3M at Polymarket. Aggregated cross-platform odds for US Election updated hourly with current probability synthesis and arbitrage detection.

Largest Spread

2.65%

Marco Rubio → View arbs

Consensus Leader

77.0%

Robert F. Kennedy Jr. +69.0%

24H Volume (Share)

$4.1M

Momentum Leader

+69.0%

Robert F. Kennedy Jr. YTD change

Probability Over Time

Hover for details · Cursor-synced tooltips

Tap "Chart settings" to adjust the chart.

Period:

Platform:

Chart settings

Aggregated (VWAP)

Volume

Kalshi

Polymarket

Gemini

Cross-Venue Spread

Current Odds Snapshot

Current probabilities across platforms with liquidity indicators

Sort:

RFK

Robert F. Kennedy Jr.

Vol $0 Spread —

Agg 77.0%

↑ +69.0%

O 77.0%

OG 77.0%

77¢

Ted Cruz

Vol $0 Spread —

Agg 69.0%

↑ +61.0%

O 69.0%

OG 69.0%

69¢

Cory Booker

Vol $0 Spread —

Agg 68.0%

↑ +60.0%

O 68.0%

OG 68.0%

68¢

JDV

J.D. Vance

Vol $57.6K Spread 2.5%

Agg 19.8%

↓ -10.5%

O 21.0%

G 20.5%

P 20.0%

K 18.5%

OG 21.0%

21¢

Gemini 20.5%

Vol $0 18–23¢

Polymarket 20.0%

Vol $50.8K 19.9–20.1¢

Kalshi 18.5%

Vol $6.8K 18–19¢

Gavin Newsom

Vol $38.0K Spread 1.8%

Agg 18.3%

↓ -0.3%

O 20.0%

K 19.0%

P 18.3%

OG 20.0%

20¢

Kalshi 19.0%

Vol $3.9K 18–20¢

Polymarket 18.3%

Vol $34.2K 18.2–18.3¢

Marco Rubio

Vol $51.9K Spread 4.9%

Agg 12.7%

↑ +8.2%

G 17.0%

K 15.5%

O 14.0%

P 12.2%

Gemini 17.0%

Vol $0 15–19¢

Kalshi 15.5%

Vol $7.8K 15–16¢

OG 14.0%

14¢

Polymarket 12.2%

Vol $44.1K 12.1–12.2¢

AOC

Alexandria Ocasio-Cortez

Vol $61.6K Spread 1.5%

Agg 4.6%

↓ -2.9%

O 6.0%

P 4.8%

K 4.5%

OG 6.0%

6¢

Polymarket 4.8%

Vol $31.2K 4.7–4.8¢

Kalshi 4.5%

Vol $30.5K 4–5¢

Kamala Harris

Vol $73.1K Spread 2.5%

Agg 3.0%

↓ -0.1%

O 5.0%

P 3.1%

K 2.5%

OG 5.0%

5¢

Polymarket 3.1%

Vol $62.9K 3–3.1¢

Kalshi 2.5%

Vol $10.2K 2–3¢

Tucker Carlson

Vol $189.9K Spread —

Agg 2.9%

↑ +1.4%

P 2.9%

Polymarket 2.9%

Vol $189.9K 2.9–3¢

Josh Shapiro

Vol $64.7K Spread 2.5%

Agg 2.5%

↑ +0.1%

O 5.0%

P 2.6%

K 2.5%

OG 5.0%

5¢

Polymarket 2.6%

Vol $20.2K 2.5–2.6¢

Kalshi 2.5%

Vol $44.5K 2–3¢

DJT

Donald J. Trump

Vol $47.3K Spread 2.6%

Agg 2.5%

↓ -0.8%

G 5.0%

K 2.5%

P 2.5%

Gemini 5.0%

Vol $0 3–7¢

Kalshi 2.5%

Vol $182 2–3¢

Polymarket 2.5%

Vol $47.1K 2.4–2.5¢

Pete Buttigieg

Vol $338.2K Spread 2.5%

Agg 1.8%

↓ -0.7%

O 4.0%

P 2.0%

K 1.5%

OG 4.0%

4¢

Polymarket 2.0%

Vol $196.9K 1.9–2¢

Kalshi 1.5%

Vol $141.3K 1–2¢

JBP

J.B. Pritzker

Vol $333.6K Spread 2.5%

Agg 1.7%

↑ +0.3%

O 4.0%

P 1.8%

K 1.5%

OG 4.0%

4¢

Polymarket 1.8%

Vol $301.8K 1.7–1.8¢

Kalshi 1.5%

Vol $31.8K 1–2¢

DTR

Dwayne 'The Rock' Johnson

Vol $70.4K Spread —

Agg 1.7%

↓ -0.4%

P 1.7%

Polymarket 1.7%

Vol $70.4K 1.6–1.8¢

Ron DeSantis

Vol $48.7K Spread 2.5%

Agg 1.5%

↑ +0.1%

O 4.0%

P 1.6%

K 1.5%

OG 4.0%

4¢

Polymarket 1.6%

Vol $4.7K 1.5–1.6¢

Kalshi 1.5%

Vol $44.0K 1–2¢

Wes Moore

Vol $411.5K Spread 0.5%

Agg 1.5%

↓ -0.1%

K 1.5%

P 1.0%

Kalshi 1.5%

Vol $399.5K 1–2¢

Polymarket 1.0%

Vol $12.0K 0.9–1¢

Gretchen Whitmer

Vol $373.4K Spread 2.9%

Agg 1.5%

↓ -0.9%

O 4.0%

K 1.5%

P 1.1%

OG 4.0%

4¢

Kalshi 1.5%

Vol $341.6K 1–2¢

Polymarket 1.1%

Vol $31.8K 1–1.1¢

Andy Beshear

Vol $2.6K Spread 1.5%

Agg 1.5%

↓ -0.4%

O 3.0%

K 1.5%

P 1.5%

OG 3.0%

3¢

Kalshi 1.5%

Vol $157 1–2¢

Polymarket 1.5%

Vol $2.5K 1.4–1.5¢

DJT

Donald J. Trump Jr.

Vol $455.1K Spread 0.6%

Agg 1.4%

↑ +0.1%

K 1.5%

P 0.9%

Kalshi 1.5%

Vol $381.2K 1–2¢

Polymarket 0.9%

Vol $73.9K 0.8–0.9¢

Ivanka Trump

Vol $24.0K Spread —

Agg 1.3%

— +0.0%

P 1.3%

Polymarket 1.3%

Vol $24.0K 1.2–1.3¢

Michelle Obama

Vol $9.0K Spread —

Agg 1.3%

↑ +0.5%

P 1.3%

Polymarket 1.3%

Vol $9.0K 1.2–1.3¢

SAS

Stephen A. Smith

Vol $407.9K Spread 0.8%

Agg 1.2%

↑ +0.3%

K 1.5%

P 0.8%

Kalshi 1.5%

Vol $224.7K 1–2¢

Polymarket 0.8%

Vol $183.2K 0.7–0.8¢

Elon Musk

Vol $20.0K Spread —

Agg 1.2%

↑ +0.1%

P 1.2%

Polymarket 1.2%

Vol $20.0K 1.1–1.2¢

Vivek Ramaswamy

Vol $17.7K Spread 3.5%

Agg 1.1%

↑ +0.2%

O 4.0%

P 1.2%

K 0.5%

OG 4.0%

4¢

Polymarket 1.2%

Vol $17.7K 1.1–1.2¢

Kalshi 0.5%

Vol $2 0–1¢

Jamie Dimon

Vol $71.6K Spread 0.6%

Agg 1.1%

↑ +0.3%

P 1.1%

K 0.5%

Polymarket 1.1%

Vol $71.6K 1–1.1¢

Kalshi 0.5%

Vol $3 0–1¢

Greg Abbott

Vol $63.8K Spread 0.4%

Agg 1.0%

↑ +0.2%

P 1.0%

K 0.5%

Polymarket 1.0%

Vol $63.8K 0.9–1¢

Kalshi 0.5%

Vol $0 0–1¢

Nikki Haley

Vol $24.2K Spread 2.5%

Agg 0.9%

↑ +0.2%

O 3.0%

P 1.0%

K 0.5%

OG 3.0%

3¢

Polymarket 1.0%

Vol $24.2K 0.9–1¢

Kalshi 0.5%

Vol $5 0–1¢

Tulsi Gabbard

Vol $44.2K Spread 2.5%

Agg 0.9%

↑ +0.2%

O 3.0%

P 1.0%

K 0.5%

OG 3.0%

3¢

Polymarket 1.0%

Vol $44.0K 0.9–1¢

Kalshi 0.5%

Vol $163 0–1¢

Kim Kardashian

Vol $47.6K Spread —

Agg 0.8%

↓ -0.1%

P 0.8%

Polymarket 0.8%

Vol $47.6K 0.7–0.8¢

Zohran Mamdani

Vol $63.1K Spread —

Agg 0.8%

↓ -0.1%

P 0.8%

Polymarket 0.8%

Vol $63.1K 0.7–0.8¢

Tim Walz

Vol $175.5K Spread 2.5%

Agg 0.7%

↓ -0.1%

O 3.0%

P 0.7%

K 0.5%

OG 3.0%

3¢

Polymarket 0.7%

Vol $175.5K 0.6–0.7¢

Kalshi 0.5%

Vol $0 0–1¢

Glenn Youngkin

Vol $159.5K Spread 2.5%

Agg 0.6%

↓ -0.2%

O 3.0%

P 0.8%

K 0.5%

OG 3.0%

3¢

Polymarket 0.8%

Vol $61.7K 0.7–0.8¢

Kalshi 0.5%

Vol $97.8K 0–1¢

LeBron James

Vol $348.5K Spread —

Agg 0.5%

↓ -0.3%

P 0.5%

Polymarket 0.5%

Vol $348.5K 0.5–0.6¢

Outcome	Aggregated	Spread	Volume	Kalshi	Polymarket	Gemini	OG
RFK Robert F. Kennedy Jr.	77.0% ↑ +69.0%	—	$0	Kalshi — —	Polymarket — —	Gemini — —	OG 77.0% 77¢
TC Ted Cruz	69.0% ↑ +61.0%	—	$0	Kalshi — —	Polymarket — —	Gemini — —	OG 69.0% 69¢
CB Cory Booker	68.0% ↑ +60.0%	—	$0	Kalshi — —	Polymarket — —	Gemini — —	OG 68.0% 68¢
JDV J.D. Vance	19.8% ↓ -10.5%	2.5%	$57.6K	Kalshi 18.5% 18–19¢ Vol $6.8K	Polymarket 20.0% 19.9–20.1¢ Vol $50.8K	Gemini 20.5% 18–23¢ Vol $0	OG 21.0% 21¢
GN Gavin Newsom	18.3% ↓ -0.3%	1.8%	$38.0K	Kalshi 19.0% 18–20¢ Vol $3.9K	Polymarket 18.3% 18.2–18.3¢ Vol $34.2K	Gemini — —	OG 20.0% 20¢
MR Marco Rubio	12.7% ↑ +8.2%	4.9%	$51.9K	Kalshi 15.5% 15–16¢ Vol $7.8K	Polymarket 12.2% 12.1–12.2¢ Vol $44.1K	Gemini 17.0% 15–19¢ Vol $0	OG 14.0% 14¢
AOC Alexandria Ocasio-Cortez	4.6% ↓ -2.9%	1.5%	$61.6K	Kalshi 4.5% 4–5¢ Vol $30.5K	Polymarket 4.8% 4.7–4.8¢ Vol $31.2K	Gemini — —	OG 6.0% 6¢
KH Kamala Harris	3.0% ↓ -0.1%	2.5%	$73.1K	Kalshi 2.5% 2–3¢ Vol $10.2K	Polymarket 3.1% 3–3.1¢ Vol $62.9K	Gemini — —	OG 5.0% 5¢
TC Tucker Carlson	2.9% ↑ +1.4%	—	$189.9K	Kalshi — —	Polymarket 2.9% 2.9–3¢ Vol $189.9K	Gemini — —	OG — —
JS Josh Shapiro	2.5% ↑ +0.1%	2.5%	$64.7K	Kalshi 2.5% 2–3¢ Vol $44.5K	Polymarket 2.6% 2.5–2.6¢ Vol $20.2K	Gemini — —	OG 5.0% 5¢
DJT Donald J. Trump	2.5% ↓ -0.8%	2.6%	$47.3K	Kalshi 2.5% 2–3¢ Vol $182	Polymarket 2.5% 2.4–2.5¢ Vol $47.1K	Gemini 5.0% 3–7¢ Vol $0	OG — —
PB Pete Buttigieg	1.8% ↓ -0.7%	2.5%	$338.2K	Kalshi 1.5% 1–2¢ Vol $141.3K	Polymarket 2.0% 1.9–2¢ Vol $196.9K	Gemini — —	OG 4.0% 4¢
JBP J.B. Pritzker	1.7% ↑ +0.3%	2.5%	$333.6K	Kalshi 1.5% 1–2¢ Vol $31.8K	Polymarket 1.8% 1.7–1.8¢ Vol $301.8K	Gemini — —	OG 4.0% 4¢
DTR Dwayne 'The Rock' Johnson	1.7% ↓ -0.4%	—	$70.4K	Kalshi — —	Polymarket 1.7% 1.6–1.8¢ Vol $70.4K	Gemini — —	OG — —
RD Ron DeSantis	1.5% ↑ +0.1%	2.5%	$48.7K	Kalshi 1.5% 1–2¢ Vol $44.0K	Polymarket 1.6% 1.5–1.6¢ Vol $4.7K	Gemini — —	OG 4.0% 4¢
WM Wes Moore	1.5% ↓ -0.1%	0.5%	$411.5K	Kalshi 1.5% 1–2¢ Vol $399.5K	Polymarket 1.0% 0.9–1¢ Vol $12.0K	Gemini — —	OG — —
GW Gretchen Whitmer	1.5% ↓ -0.9%	2.9%	$373.4K	Kalshi 1.5% 1–2¢ Vol $341.6K	Polymarket 1.1% 1–1.1¢ Vol $31.8K	Gemini — —	OG 4.0% 4¢
AB Andy Beshear	1.5% ↓ -0.4%	1.5%	$2.6K	Kalshi 1.5% 1–2¢ Vol $157	Polymarket 1.5% 1.4–1.5¢ Vol $2.5K	Gemini — —	OG 3.0% 3¢
DJT Donald J. Trump Jr.	1.4% ↑ +0.1%	0.6%	$455.1K	Kalshi 1.5% 1–2¢ Vol $381.2K	Polymarket 0.9% 0.8–0.9¢ Vol $73.9K	Gemini — —	OG — —
IT Ivanka Trump	1.3% — +0.0%	—	$24.0K	Kalshi — —	Polymarket 1.3% 1.2–1.3¢ Vol $24.0K	Gemini — —	OG — —
MO Michelle Obama	1.3% ↑ +0.5%	—	$9.0K	Kalshi — —	Polymarket 1.3% 1.2–1.3¢ Vol $9.0K	Gemini — —	OG — —
SAS Stephen A. Smith	1.2% ↑ +0.3%	0.8%	$407.9K	Kalshi 1.5% 1–2¢ Vol $224.7K	Polymarket 0.8% 0.7–0.8¢ Vol $183.2K	Gemini — —	OG — —
EM Elon Musk	1.2% ↑ +0.1%	—	$20.0K	Kalshi — —	Polymarket 1.2% 1.1–1.2¢ Vol $20.0K	Gemini — —	OG — —
VR Vivek Ramaswamy	1.1% ↑ +0.2%	3.5%	$17.7K	Kalshi 0.5% 0–1¢ Vol $2	Polymarket 1.2% 1.1–1.2¢ Vol $17.7K	Gemini — —	OG 4.0% 4¢
JD Jamie Dimon	1.1% ↑ +0.3%	0.6%	$71.6K	Kalshi 0.5% 0–1¢ Vol $3	Polymarket 1.1% 1–1.1¢ Vol $71.6K	Gemini — —	OG — —
GA Greg Abbott	1.0% ↑ +0.2%	0.4%	$63.8K	Kalshi 0.5% 0–1¢ Vol $0	Polymarket 1.0% 0.9–1¢ Vol $63.8K	Gemini — —	OG — —
NH Nikki Haley	0.9% ↑ +0.2%	2.5%	$24.2K	Kalshi 0.5% 0–1¢ Vol $5	Polymarket 1.0% 0.9–1¢ Vol $24.2K	Gemini — —	OG 3.0% 3¢
TG Tulsi Gabbard	0.9% ↑ +0.2%	2.5%	$44.2K	Kalshi 0.5% 0–1¢ Vol $163	Polymarket 1.0% 0.9–1¢ Vol $44.0K	Gemini — —	OG 3.0% 3¢
KK Kim Kardashian	0.8% ↓ -0.1%	—	$47.6K	Kalshi — —	Polymarket 0.8% 0.7–0.8¢ Vol $47.6K	Gemini — —	OG — —
ZM Zohran Mamdani	0.8% ↓ -0.1%	—	$63.1K	Kalshi — —	Polymarket 0.8% 0.7–0.8¢ Vol $63.1K	Gemini — —	OG — —
TW Tim Walz	0.7% ↓ -0.1%	2.5%	$175.5K	Kalshi 0.5% 0–1¢ Vol $0	Polymarket 0.7% 0.6–0.7¢ Vol $175.5K	Gemini — —	OG 3.0% 3¢
GY Glenn Youngkin	0.6% ↓ -0.2%	2.5%	$159.5K	Kalshi 0.5% 0–1¢ Vol $97.8K	Polymarket 0.8% 0.7–0.8¢ Vol $61.7K	Gemini — —	OG 3.0% 3¢
LJ LeBron James	0.5% ↓ -0.3%	—	$348.5K	Kalshi — —	Polymarket 0.5% 0.5–0.6¢ Vol $348.5K	Gemini — —	OG — —

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
MR Marco Rubio	Polymarket → Kalshi	Buy @ P 12.2¢	Sell @ K 15¢	+2.80%	+2.65%	Yes
JDV J.D. Vance	Kalshi → Polymarket	Buy @ K 19¢	Sell @ P 19.9¢	+0.90%	+0.71%	No
DJT Donald J. Trump	Polymarket → Gemini	Buy @ P 2.5¢	Sell @ G 3¢	+0.50%	+0.49%	No
SAS Stephen A. Smith	Polymarket → Kalshi	Buy @ P 0.8¢	Sell @ K 1¢	+0.20%	+0.13%	No
DJT Donald J. Trump Jr.	Polymarket → Kalshi	Buy @ P 0.9¢	Sell @ K 1¢	+0.10%	+0.03%	No
VR Vivek Ramaswamy	Kalshi → Polymarket	Buy @ K 1¢	Sell @ P 1.1¢	+0.10%	+0.03%	No
KH Kamala Harris	Kalshi → Polymarket	Buy @ K 3¢	Sell @ P 3¢	+0.00%	-0.07%	No
WM Wes Moore	Polymarket → Kalshi	Buy @ P 1¢	Sell @ K 1¢	+0.00%	-0.07%	No
JD Jamie Dimon	Kalshi → Polymarket	Buy @ K 1¢	Sell @ P 1¢	+0.00%	-0.07%	No
GW Gretchen Whitmer	Polymarket → Kalshi	Buy @ P 1.1¢	Sell @ K 1¢	-0.10%	-0.17%	No
PB Pete Buttigieg	Kalshi → Polymarket	Buy @ K 2¢	Sell @ P 1.9¢	-0.10%	-0.17%	No
GA Greg Abbott	Kalshi → Polymarket	Buy @ K 1¢	Sell @ P 0.9¢	-0.10%	-0.17%	No
NH Nikki Haley	Kalshi → Polymarket	Buy @ K 1¢	Sell @ P 0.9¢	-0.10%	-0.17%	No
TG Tulsi Gabbard	Kalshi → Polymarket	Buy @ K 1¢	Sell @ P 0.9¢	-0.10%	-0.17%	No
JBP J.B. Pritzker	Kalshi → Polymarket	Buy @ K 2¢	Sell @ P 1.7¢	-0.30%	-0.37%	No
GY Glenn Youngkin	Kalshi → Polymarket	Buy @ K 1¢	Sell @ P 0.7¢	-0.30%	-0.37%	No
GN Gavin Newsom	Polymarket → Kalshi	Buy @ P 18.3¢	Sell @ K 18¢	-0.30%	-0.48%	No
AOC Alexandria Ocasio-Cortez	Kalshi → Polymarket	Buy @ K 5¢	Sell @ P 4.7¢	-0.30%	-0.37%	No
TW Tim Walz	Kalshi → Polymarket	Buy @ K 1¢	Sell @ P 0.6¢	-0.40%	-0.47%	No
JS Josh Shapiro	Kalshi → Polymarket	Buy @ K 3¢	Sell @ P 2.5¢	-0.50%	-0.57%	No
AB Andy Beshear	Polymarket → Kalshi	Buy @ P 1.5¢	Sell @ K 1¢	-0.50%	-0.57%	No
RD Ron DeSantis	Kalshi → Polymarket	Buy @ K 2¢	Sell @ P 1.5¢	-0.50%	-0.57%	No

Outcome Diff

Outcome A	Outcome B	Venue	A Odds	B Odds	Diff	Strategy
JDV J.D. Vance	JBP J.B. Pritzker	Polymarket	A 20.0%	B 1.8%	+18.25%	Buy spread
JDV J.D. Vance	PB Pete Buttigieg	Polymarket	A 20.0%	B 2.0%	+18.05%	Buy spread
JDV J.D. Vance	DJT Donald J. Trump	Polymarket	A 20.0%	B 2.5%	+17.55%	Buy spread
GN Gavin Newsom	PB Pete Buttigieg	Kalshi	A 19.0%	B 1.5%	+17.50%	Buy spread
GN Gavin Newsom	JBP J.B. Pritzker	Kalshi	A 19.0%	B 1.5%	+17.50%	Buy spread
GN Gavin Newsom	RD Ron DeSantis	Kalshi	A 19.0%	B 1.5%	+17.50%	Buy spread
JDV J.D. Vance	JS Josh Shapiro	Polymarket	A 20.0%	B 2.6%	+17.45%	Buy spread
JDV J.D. Vance	TC Tucker Carlson	Polymarket	A 20.0%	B 2.9%	+17.05%	Buy spread
JDV J.D. Vance	PB Pete Buttigieg	Kalshi	A 18.5%	B 1.5%	+17.00%	Buy spread
JDV J.D. Vance	JBP J.B. Pritzker	Kalshi	A 18.5%	B 1.5%	+17.00%	Buy spread
JDV J.D. Vance	RD Ron DeSantis	Kalshi	A 18.5%	B 1.5%	+17.00%	Buy spread
JDV J.D. Vance	KH Kamala Harris	Polymarket	A 20.0%	B 3.1%	+16.95%	Buy spread
GN Gavin Newsom	KH Kamala Harris	Kalshi	A 19.0%	B 2.5%	+16.50%	Buy spread
GN Gavin Newsom	JS Josh Shapiro	Kalshi	A 19.0%	B 2.5%	+16.50%	Buy spread
GN Gavin Newsom	DJT Donald J. Trump	Kalshi	A 19.0%	B 2.5%	+16.50%	Buy spread
GN Gavin Newsom	JBP J.B. Pritzker	Polymarket	A 18.3%	B 1.8%	+16.50%	Buy spread
GN Gavin Newsom	PB Pete Buttigieg	Polymarket	A 18.3%	B 2.0%	+16.30%	Buy spread
JDV J.D. Vance	KH Kamala Harris	Kalshi	A 18.5%	B 2.5%	+16.00%	Buy spread
JDV J.D. Vance	JS Josh Shapiro	Kalshi	A 18.5%	B 2.5%	+16.00%	Buy spread
JDV J.D. Vance	DJT Donald J. Trump	Kalshi	A 18.5%	B 2.5%	+16.00%	Buy spread
GN Gavin Newsom	DJT Donald J. Trump	Polymarket	A 18.3%	B 2.5%	+15.80%	Buy spread
GN Gavin Newsom	JS Josh Shapiro	Polymarket	A 18.3%	B 2.6%	+15.70%	Buy spread
JDV J.D. Vance	DJT Donald J. Trump	Gemini	A 20.5%	B 5.0%	+15.50%	Buy spread
GN Gavin Newsom	TC Tucker Carlson	Polymarket	A 18.3%	B 2.9%	+15.30%	Buy spread
JDV J.D. Vance	AOC Alexandria Ocasio-Cortez	Polymarket	A 20.0%	B 4.8%	+15.25%	Buy spread
GN Gavin Newsom	KH Kamala Harris	Polymarket	A 18.3%	B 3.1%	+15.20%	Buy spread
GN Gavin Newsom	AOC Alexandria Ocasio-Cortez	Kalshi	A 19.0%	B 4.5%	+14.50%	Buy spread
JDV J.D. Vance	AOC Alexandria Ocasio-Cortez	Kalshi	A 18.5%	B 4.5%	+14.00%	Buy spread
MR Marco Rubio	PB Pete Buttigieg	Kalshi	A 15.5%	B 1.5%	+14.00%	Buy spread
MR Marco Rubio	JBP J.B. Pritzker	Kalshi	A 15.5%	B 1.5%	+14.00%	Buy spread

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).

Gemini: Public Prediction Markets + ticker endpoints (best bid/ask + last + 24H USD volume when available).

OG: Public OG contracts endpoint (Yes/No chance from contract data; no provider 24H volume field in this payload).

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.