The Prediction Markets

Maine Senate winner? (Person)

Closes
Jul 7, 2027, in 9 months
Traded
$15.3M
Venues
Polymarket, Kalshi
Prices updated
just now
Share

What the markets expect

Democratic 66.1%

Next is Troy Jackson at 65%. The venues differ most on Republican (Polymarket 33%, Kalshi 36%), a 3.0-point gap.

Odds by venue

Consensus blends each venue’s last price, weighted by how much has traded there. Best Yes price is the cheapest ask across venues, and the payout is what a winning $100 stake returns before fees. Open a row for each venue’s contract name, bid and ask, and how closely their rules match.

2 of 20 prices are live from the exchange feeds; the rest come from our regular price polls. Ages are as of when this page was built.

  • Polymarket
  • Kalshi
Democratic
66.1%
Polymarket 66.5%live, just nowKalshi 66%live, just nowBest Yes 66¢ on Kalshi, $100 pays $152 (1.52x)
Polymarket
Contract
Troy Jackson (D)
Price
66.5%
As of
Live feed, just now
Buy Yes
67¢
Sell Yes
66¢
$100 on Yes pays
$149 (1.49x)
Volume
$1.3M
Trade this on Polymarket
Kalshi
Contract
Troy Jackson
Price
66%
As of
Live feed, just now
Buy Yes
66¢
Sell Yes
65¢
$100 on Yes pays
$152 (1.52x)
Volume
$4.5M
Trade this on Kalshi
Partial parity

Payoffs match in ordinary outcomes; see the rule differences below the table.

No arbitrage: the best bid elsewhere is 66¢, at or below the cheapest ask of 66¢.

Troy Jackson
65%
Kalshi 65%polled, 40s agoBest Yes 66¢ on Kalshi, $100 pays $152 (1.52x)
Kalshi
Contract
Troy Jackson
Last price
65%
As of
Polled just now
Buy Yes
66¢
Sell Yes
65¢
$100 on Yes pays
$152 (1.52x)
Volume
$771K
Trade this on Kalshi
RepublicanArb
35.3%
Polymarket 33%polled, 40s agoKalshi 36%polled, 40s agoBest Yes 34¢ on Polymarket, $100 pays $294 (2.94x)
Polymarket
Contract
Susan Collins (R)
Last price
33%
As of
Polled just now
Buy Yes
34¢
Sell Yes
32¢
$100 on Yes pays
$294 (2.94x)
Volume
$1.1M
Trade this on Polymarket
Kalshi
Contract
Susan Collins
Last price
36%
As of
Polled just now
Buy Yes
36¢
Sell Yes
35¢
$100 on Yes pays
$278 (2.78x)
Volume
$5.3M
Trade this on Kalshi
Partial parity

Payoffs match in ordinary outcomes; see the rule differences below the table.

Buying on Polymarket at 34¢ and selling on Kalshi at 35¢ nets 100 bps before fees.

Susan Collins
35%
Kalshi 35%polled, 40s agoBest Yes 35¢ on Kalshi, $100 pays $286 (2.86x)
Kalshi
Contract
Susan Collins
Last price
35%
As of
Polled just now
Buy Yes
35¢
Sell Yes
34¢
$100 on Yes pays
$286 (2.86x)
Volume
$1.0M
Trade this on Kalshi
Angus King
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.2¢ on Kalshi, $100 pays $50,000 (500x)
Kalshi
Contract
Angus King
Last price
0.1%
As of
Polled just now
Buy Yes
0.2¢
Sell Yes
—
$100 on Yes pays
$50,000 (500x)
Trade this on Kalshi
Angus King III
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Angus King III
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$20K
Trade this on Kalshi
Brian Bryant
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Brian Bryant
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$26K
Trade this on Kalshi
Dan Kleban
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Dan Kleban
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$109K
Trade this on Kalshi
Graham Platner
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Graham Platner
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$364K
Trade this on Kalshi
Janet Mills
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Janet Mills
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$106K
Trade this on Kalshi
Show 8 more outcomes
Jared Golden
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Jared Golden
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$80K
Trade this on Kalshi
Mattie Daughtrey
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Mattie Daughtrey
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$29K
Trade this on Kalshi
Nirav Shah
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Nirav Shah
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$183K
Trade this on Kalshi
Patrick Dempsey
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Patrick Dempsey
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$65K
Trade this on Kalshi
Sara Gideon
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Sara Gideon
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$38K
Trade this on Kalshi
Shenna Bellows
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Shenna Bellows
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$122K
Trade this on Kalshi
Stephen King
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Stephen King
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$8K
Trade this on Kalshi
Valli Geiger
0.1%
Kalshi 0.1%polled, 40s agoBest Yes 0.1¢ on Kalshi, $100 pays $100,000 (1000x)
Kalshi
Contract
Valli Geiger
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$66K
Trade this on Kalshi

Possible arbitrage before fees: buy Republican on Polymarket at 34¢, sell on Kalshi at 35¢ (100 bps). Check the rules below before trading. See all live spreads

Mostly the same bet: 4 differences

Where they differ

  • Kalshi settles on the party of the officeholder sworn in/inaugurated for the new term; Polymarket settles on the party of the called winner. They differ if the winner dies, withdraws or is not seated before the term starts.
  • Independents: Polymarket assigns a non-affiliated winner by stated caucus (House) or excludes independents from party options (Senate/Governor); Kalshi requires party membership.
  • Kalshi may close early on a media-consensus projection; Polymarket resolves on consensus calls with certification as the fallback.
  • Trading closes at different times: Nov 4, 2026, 4:59 AM UTC on Polymarket and Nov 3, 2027, 3:00 PM UTC on Kalshi.
Polymarket
Polymarket resolves via:
UMA optimistic oracle
Kalshi
Kalshi resolves via:
Kalshi (CFTC-regulated exchange), source: United States Congress, Maine Secretary of State
Show full rule comparison
  • Kalshi settles on the party of the officeholder sworn in/inaugurated for the new term; Polymarket settles on the party of the called winner. They differ if the winner dies, withdraws or is not seated before the term starts.
  • Independents: Polymarket assigns a non-affiliated winner by stated caucus (House) or excludes independents from party options (Senate/Governor); Kalshi requires party membership.
  • Kalshi may close early on a media-consensus projection; Polymarket resolves on consensus calls with certification as the fallback.
  • Trading closes Nov 4, 2026, 4:59 AM UTC on Polymarket and Nov 3, 2027, 3:00 PM UTC on Kalshi.

Summarized from each venue’s published rules; the venue’s own rules page is the final word.

How the odds have moved

The top 3 outcomes on both venues, with the consensus between them. Hover for exact values.

  • Democratic
  • Troy Jackson
  • Republican

Live prices for Democratic

What it costs to buy Yes, what you would get selling it, and the last trade on each exchange, updating as orders change. Hover a status for timing details.

Order books

Each venue’s resting orders for the selected outcome’s Yes contract, side by side. Top of book streams live; depth refreshes every 15 seconds.

Combined depth · both venues

Loading both order books…

Polymarket

Open on Polymarket ↗

Top of book

Connecting
Best bid
—
Spread
—
Best ask
—

Waiting for the first live quote…

Depth · top 8 levels

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Recent trades

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Kalshi

Open on Kalshi ↗

Top of book

Connecting
Best bid
—
Spread
—
Best ask
—

Waiting for the first live quote…

Depth · top 8 levels

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Recent trades

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What your stake buys

Enter a stake to see where it buys the most after fees, using each venue’s live order book.

$
Buy

Loading both order books…

Buys at the asks resting now (taker orders), cheapest after fees first, from order-book snapshots up to 15 seconds old. Fees: Kalshi 0.07 × price × (1 − price) per share, rounded up to the cent; Polymarket 0.04 × price × (1 − price) per share (politics rate). Fee calculator. Estimates only, not advice.

About this market

Live prediction market odds for "Maine Senate winner? (Person)". Democratic leads at 66.1%. Next is Troy Jackson at 65%. $15.3M has traded across 18 outcomes on Kalshi and Polymarket. The market is expected to resolve by Jul 7, 2027.

Questions

What does the consensus price mean?

It is the price of a Yes contract that pays $1 if the outcome happens. A 14¢ price means traders put the chance near 14%. Where two venues list the same outcome, we blend their last prices, weighting the venue with more trading volume more heavily (neither counts for less than a quarter). When only one outcome can win, each venue’s prices add up to a little over 100% (its margin); the fair chance removes that margin so the outcomes add up to exactly 100%.

How is the payout worked out?

A Yes contract pays $1 if it wins, so at the best ask a $100 stake buys 100 ÷ ask contracts. At 18¢ that is about 555 contracts, paying $556 (5.56x) if Yes happens. Venue fees and price slippage on larger orders are not included.

Why do the venues show different prices?

Each venue has its own traders, fees and order book. Contracts can also settle on slightly different terms, which is why each row lists how closely the rules match.

Is a price gap an arbitrage?

Only when you can buy Yes on one venue below what someone pays for Yes on the other, after fees, and both contracts settle the same way. We show the executable bid and ask so you can check.

How fresh are these prices?

Venue prices refresh every few minutes, and the order book and live quotes stream continuously. Each venue’s card shows when we last observed it.

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