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Which Senators will vote for the Clarity Act? Mike Lee

Mike Lee votes Yea on the first Senate vote on final passage of the Clarity Act crypto market structure bill before Jan 1, 2027. Listed on both Kalshi and Polymarket; recorded continuously since Sep 15, 2026. Live.

kalshi
4.5¢
bid 0.02 · ask 0.07 · Sep 19, 10:50 AM ET
polymarket
10.0¢
bid 0.09 · ask 0.11 · Sep 19, 5:57 AM ET

Current gap between the two mids: 5.5¢. Over the last 7 days the two venues differed by 4.9% on average and 16.3% at most.

Price history, both venues (7 days)

kalshipolymarket
3.6%5.5%7.5%9.4%11.4%18:0000:5607:5314:50kalshipolymarket
Data table
time (UTC)kalshi midpolymarket mid
Sep 18 18:005.1%10.5%
Sep 18 18:056.5%10.5%
Sep 18 18:107.0%10.3%
Sep 18 18:307.0%10.0%
Sep 18 18:357.0%10.0%
Sep 18 18:407.0%10.0%
Sep 18 18:557.0%
Sep 18 20:007.0%
Sep 18 20:157.0%
Sep 18 20:207.0%
Sep 18 20:456.0%
Sep 18 20:505.0%
Sep 18 21:006.5%
Sep 18 21:056.7%
Sep 18 21:107.0%
Sep 18 21:157.0%
Sep 18 22:007.0%
Sep 18 22:057.0%
Sep 18 22:107.0%
Sep 18 22:157.0%
Sep 18 23:357.0%
Sep 19 00:007.0%
Sep 19 01:557.0%
Sep 19 02:007.0%
Sep 19 02:507.0%
Sep 19 03:507.0%
Sep 19 04:107.0%
Sep 19 05:357.0%
Sep 19 07:157.0%
Sep 19 07:307.0%
Sep 19 08:107.0%
Sep 19 09:007.0%
Sep 19 09:507.0%
Sep 19 09:557.0%
Sep 19 10:057.0%
Sep 19 10:107.0%
Sep 19 10:257.0%
Sep 19 10:307.0%
Sep 19 10:357.0%
Sep 19 10:457.0%
Sep 19 11:257.0%
Sep 19 11:307.0%
Sep 19 11:357.0%
Sep 19 12:207.0%
Sep 19 13:106.7%
Sep 19 13:154.8%
Sep 19 13:205.3%
Sep 19 13:255.0%
Sep 19 13:304.6%
Sep 19 13:354.5%
Sep 19 14:004.5%
Sep 19 14:504.5%

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.

Disagreement windows
19
beyond fees, at size
Largest net edge
5.84%
avg 0.62%
Typical window
47 min
longest 333 min
Last window
Sep 19, 2026
first Sep 15, 2026

Recent disagreement windows

OpenedClosedLengthScansMax net edge
Sep 19, 10:50 AM ETSep 19, 10:50 AM ET0 min10.58%
Sep 19, 9:14 AM ETSep 19, 10:02 AM ET48 min140.58%
Sep 18, 6:00 PM ETSep 18, 6:53 PM ET54 min131.05%
Sep 18, 4:03 PM ETSep 18, 5:19 PM ET76 min141.05%
Sep 18, 9:26 AM ETSep 18, 2:58 PM ET5.5 h1602.12%
Sep 18, 1:47 AM ETSep 18, 2:58 AM ET70 min422.19%
Sep 17, 11:57 PM ETSep 18, 12:56 AM ET59 min152.23%
Sep 17, 10:34 PM ETSep 17, 10:39 PM ET5 min31.56%
Sep 17, 9:11 PM ETSep 17, 9:16 PM ET5 min31.56%
Sep 17, 6:34 PM ETSep 17, 6:39 PM ET5 min41.56%

Related markets on both venues

Frequently asked questions

What are the current Kalshi and Polymarket odds for "Which Senators will vote for the Clarity Act? Mike Lee"?

As of the latest recorded books, Kalshi's YES mid is 4.5¢ (bid 0.02, ask 0.07) and Polymarket's is 10.0¢ (bid 0.09, ask 0.11) — a 5.5¢ gap. Prices are recorded continuously; this page refreshes every few minutes.

Has this market been an arbitrage?

Yes — 19 separate windows where buying the cheaper side on each venue cost less than $1 after both fees, first on Sep 15, 2026 and most recently Sep 19, 2026. The largest net edge was 5.84% and windows averaged 47 minutes.

Do both contracts resolve the same way?

The pair was confirmed as the same question (AI-matched · 95%). 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 · 95%. Verify both markets' rules yourself; this is data, not advice.