2028 Republican presidential nominee Thomas Massie
Thomas Massie wins and accepts the 2028 Republican presidential nomination. Listed on both Kalshi and Polymarket; recorded continuously since Aug 10, 2026. Live.
Current gap between the two mids: 0.6¢. Over the last 7 days the two venues differed by 0.5% on average and 0.6% at most.
Price history, both venues (7 days)
Data table
| time (UTC) | kalshi mid | polymarket mid |
|---|---|---|
| Sep 18 10:20 | 1.2% | 0.7% |
| Sep 18 10:40 | 1.2% | 0.7% |
| Sep 18 10:50 | 1.2% | 0.7% |
| Sep 18 11:05 | 1.2% | 0.7% |
| Sep 18 11:15 | 1.2% | 0.7% |
| Sep 18 11:25 | 1.2% | 0.7% |
| Sep 18 12:20 | 1.2% | 0.7% |
| Sep 18 12:45 | 1.2% | 0.7% |
| Sep 18 13:10 | 1.2% | 0.7% |
| Sep 18 13:55 | 1.2% | 0.7% |
| Sep 18 14:25 | 1.2% | 0.7% |
| Sep 18 14:50 | 1.2% | 0.7% |
| Sep 18 15:30 | 1.2% | 0.7% |
| Sep 18 15:35 | 1.2% | 0.7% |
| Sep 18 16:40 | 1.2% | 0.7% |
| Sep 18 17:05 | 1.2% | 0.7% |
| Sep 18 17:10 | 1.2% | 0.7% |
| Sep 18 18:00 | 1.2% | 0.7% |
| Sep 18 18:15 | 1.2% | 0.7% |
| Sep 18 18:30 | 1.2% | 0.7% |
| Sep 18 18:55 | 1.3% | 0.7% |
| Sep 18 19:10 | 1.3% | 0.7% |
| Sep 18 19:15 | 1.3% | 0.7% |
| Sep 18 19:40 | 1.3% | 0.7% |
| Sep 18 19:55 | 1.3% | 0.7% |
| Sep 18 20:00 | 1.3% | 0.7% |
| Sep 18 20:10 | 1.3% | 0.7% |
| Sep 18 20:15 | 1.3% | 0.7% |
| Sep 18 20:20 | 1.3% | 0.7% |
| Sep 18 20:35 | 1.3% | 0.7% |
| Sep 18 20:45 | 1.3% | 0.7% |
| Sep 18 20:50 | 1.3% | 0.7% |
| Sep 18 21:35 | 1.3% | 0.7% |
| Sep 18 22:25 | 1.3% | 0.7% |
| Sep 18 22:30 | 1.3% | 0.7% |
| Sep 18 22:40 | 1.3% | 0.7% |
| Sep 18 22:45 | 1.3% | 0.7% |
| Sep 18 22:55 | 1.3% | 0.7% |
| Sep 18 23:55 | 1.3% | 0.7% |
| Sep 19 00:05 | 1.2% | 0.7% |
| Sep 19 00:15 | 1.2% | 0.7% |
| Sep 19 00:20 | 1.2% | — |
| Sep 19 01:25 | 1.2% | — |
| Sep 19 01:35 | 1.2% | — |
| Sep 19 02:20 | 1.2% | — |
| Sep 19 02:35 | 1.2% | — |
| Sep 19 02:40 | 1.2% | — |
| Sep 19 03:00 | 1.2% | — |
| Sep 19 03:20 | 1.2% | — |
| Sep 19 03:45 | 1.2% | — |
| Sep 19 04:10 | 1.2% | — |
| Sep 19 04:35 | 1.2% | — |
| Sep 19 05:35 | 1.2% | — |
| Sep 19 05:50 | 1.2% | — |
| Sep 19 05:55 | 1.2% | — |
| Sep 19 07:10 | 1.2% | — |
| Sep 19 07:30 | 1.2% | — |
| Sep 19 07:35 | 1.2% | — |
| Sep 19 07:50 | 1.2% | — |
| Sep 19 08:30 | 1.2% | — |
| Sep 19 08:50 | 1.2% | — |
| Sep 19 08:55 | 1.2% | — |
| Sep 19 09:00 | 1.2% | — |
| Sep 19 09:15 | 1.2% | — |
| Sep 19 09:55 | 1.2% | — |
| Sep 19 10:05 | 1.2% | — |
Mid price of the YES side per venue, 5-minute buckets, from continuously recorded order books. Breaks mean the recorder was down or a book was empty.
Recent disagreement windows
| Opened | Closed | Length | Scans | Max net edge |
|---|---|---|---|---|
| Sep 18, 7:57 PM ET | Sep 18, 8:05 PM ET | 8 min | 2 | 0.24% |
| Sep 18, 6:26 PM ET | Sep 18, 6:55 PM ET | 29 min | 5 | 0.24% |
| Sep 18, 5:35 PM ET | Sep 18, 5:37 PM ET | 2 min | 3 | 0.24% |
| Sep 18, 2:03 PM ET | Sep 18, 4:54 PM ET | 2.8 h | 24 | 0.24% |
| Sep 18, 9:59 AM ET | Sep 18, 1:23 PM ET | 3.4 h | 27 | 0.24% |
| Sep 18, 8:24 AM ET | Sep 18, 9:11 AM ET | 46 min | 3 | 0.24% |
| Sep 18, 6:05 AM ET | Sep 18, 7:26 AM ET | 81 min | 8 | 0.24% |
| Sep 18, 3:31 AM ET | Sep 18, 5:30 AM ET | 2.0 h | 14 | 0.25% |
| Sep 18, 2:45 AM ET | Sep 18, 2:45 AM ET | 0 min | 1 | 0.24% |
| Sep 18, 1:34 AM ET | Sep 18, 2:11 AM ET | 37 min | 3 | 0.24% |
Related markets on both venues
Frequently asked questions
What are the current Kalshi and Polymarket odds for "2028 Republican presidential nominee Thomas Massie"?
As of the latest recorded books, Kalshi's YES mid is 1.2¢ (bid 0.011, ask 0.013) and Polymarket's is 0.6¢ (bid 0.006, ask 0.007) — a 0.6¢ gap. Prices are recorded continuously; this page refreshes every few minutes.
Has this market been an arbitrage?
Yes — 133 separate windows where buying the cheaper side on each venue cost less than $1 after both fees, first on Aug 10, 2026 and most recently Sep 19, 2026. The largest net edge was 0.38% and windows averaged 138 minutes.
Do both contracts resolve the same way?
The pair was confirmed as the same question (AI-matched · 98%). That judgment covers the headline question; resolution rules can still differ in edge cases (sources, timing, ties). Read both venues' rules before treating a gap as risk-free.
What do the fees do to the gap?
Kalshi charges takers 7% × price × (1 − price) per contract; Polymarket charges its category rate on the same curve. Near 50¢ that is roughly 1.75¢ per contract on Kalshi and 1–1.75¢ on Polymarket, so a visible gap of 3–4¢ is typically the minimum before anything is left.
← every Kalshi↔Polymarket pair · resolution criteria · taker fees · match: AI-matched · 98%. Verify both markets' rules yourself; this is data, not advice.