The Prediction Markets

How many House seats will the Democrats win in Pennsylvania?

Closes
Nov 4, 2026, in 12 days
Traded
$90K
Venues
Polymarket, Kalshi
Prices updated
1 min ago
Share

What the markets expect

11 32.1%

Next is 10 at 27.5%. The venues differ most on 12+ (Polymarket 2.9%, Kalshi 12%), a 9.2-point gap.

11 32.1%10 27.5%9 18.1%12+ 8.4%8 5.9%3 others 8%

Odds by venue

Fair chance strips out each venue’s built-in margin (its prices add up to more than 100%), then blends the venues by how much has traded there, so the outcomes add up to 100%. 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.

Prices come from our regular polls of each venue, the oldest 3 min ago. Ages are as of when this page was built.

  • Polymarket
  • Kalshi
11
32.1%
Polymarket 37.5%(35.4% fair)polled, 3 min agoKalshi 36%(31% fair)polled, 1 min agoBest Yes 38¢ on Polymarket, $100 pays $263 (2.63x)
Polymarket
Contract
11
Last price
37.5%
Fair, margin removed
35.4%
As of
Polled 3 min ago
Buy Yes
38¢
Sell Yes
37¢
$100 on Yes pays
$263 (2.63x)
Volume
$8K
Trade this on Polymarket
Kalshi
Contract
11
Last price
36%
Fair, margin removed
31%
As of
Polled 1 min ago
Buy Yes
40¢
Sell Yes
36¢
$100 on Yes pays
$250 (2.50x)
Volume
$18K
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 36¢, at or below the cheapest ask of 38¢.

10
27.5%
Polymarket 30.5%(28.8% fair)polled, 3 min agoKalshi 31%(26.7% fair)polled, 1 min agoBest Yes 31¢ on Polymarket, $100 pays $323 (3.23x)
Polymarket
Contract
10
Last price
30.5%
Fair, margin removed
28.8%
As of
Polled 3 min ago
Buy Yes
31¢
Sell Yes
30¢
$100 on Yes pays
$323 (3.23x)
Volume
$5K
Trade this on Polymarket
Kalshi
Contract
10
Last price
31%
Fair, margin removed
26.7%
As of
Polled 1 min ago
Buy Yes
33¢
Sell Yes
31¢
$100 on Yes pays
$303 (3.03x)
Volume
$7K
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 31¢, at or below the cheapest ask of 31¢.

9
18.1%
Polymarket 19.5%(18.4% fair)polled, 3 min agoKalshi 21%(18.1% fair)polled, 1 min agoBest Yes 20¢ on Polymarket, $100 pays $500 (5.00x)
Polymarket
Contract
9
Last price
19.5%
Fair, margin removed
18.4%
As of
Polled 3 min ago
Buy Yes
20¢
Sell Yes
19¢
$100 on Yes pays
$500 (5.00x)
Volume
$4K
Trade this on Polymarket
Kalshi
Contract
9
Last price
21%
Fair, margin removed
18.1%
As of
Polled 1 min ago
Buy Yes
21¢
Sell Yes
19¢
$100 on Yes pays
$476 (4.76x)
Volume
$5K
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 19¢, at or below the cheapest ask of 20¢.

12+
8.4%
Polymarket 2.9%polled, 3 min agoKalshi 12%(10.3% fair)polled, 1 min agoBest Yes 2.9¢ on Polymarket, $100 pays $3,448 (34.5x)
Polymarket
Contract
12+
Last price
2.9%
As of
Polled 3 min ago
Buy Yes
2.9¢
Sell Yes
2.8¢
$100 on Yes pays
$3,448 (34.5x)
Volume
$1K
Trade this on Polymarket
Kalshi
Contract
12
Last price
12%
Fair, margin removed
10.3%
As of
Polled 1 min ago
Buy Yes
12¢
Sell Yes
2¢
$100 on Yes pays
$833 (8.33x)
Volume
$9K
Trade this on Kalshi
Same label, rules unverified

Labels suggest the same named outcome; no persisted outcome identity or settlement parity is verified.

No arbitrage: the best bid elsewhere is 2¢, at or below the cheapest ask of 2.9¢.

8
5.9%
Polymarket 6%polled, 3 min agoKalshi 7%(6% fair)polled, 1 min agoBest Yes 7¢ on Polymarket, $100 pays $1,429 (14.3x)
Polymarket
Contract
8
Last price
6%
As of
Polled 3 min ago
Buy Yes
7¢
Sell Yes
5¢
$100 on Yes pays
$1,429 (14.3x)
Volume
$2K
Trade this on Polymarket
Kalshi
Contract
8
Last price
7%
Fair, margin removed
6%
As of
Polled 1 min ago
Buy Yes
7¢
Sell Yes
4¢
$100 on Yes pays
$1,429 (14.3x)
Volume
$4K
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 5¢, at or below the cheapest ask of 7¢.

Above 12
5.1%
Kalshi 6%(5.2% fair)polled, 1 min agoBest Yes 11¢ on Kalshi, $100 pays $909 (9.09x)
Kalshi
Contract
Above 12
Last price
6%
Fair, margin removed
5.2%
As of
Polled 1 min ago
Buy Yes
11¢
Sell Yes
2¢
$100 on Yes pays
$909 (9.09x)
Volume
$5K
Trade this on Kalshi
7
2.2%
Polymarket 3.7%polled, 3 min agoKalshi 2%polled, 1 min agoBest Yes 3.7¢ on Polymarket, $100 pays $2,703 (27.0x)
Polymarket
Contract
7
Last price
3.7%
As of
Polled 3 min ago
Buy Yes
3.7¢
Sell Yes
3.6¢
$100 on Yes pays
$2,703 (27.0x)
Volume
$5K
Trade this on Polymarket
Kalshi
Contract
7
Last price
2%
As of
Polled 1 min ago
Buy Yes
4¢
Sell Yes
2¢
$100 on Yes pays
$2,500 (25.0x)
Volume
$12K
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 3.6¢, at or below the cheapest ask of 4¢.

Below 7
0.7%
Polymarket 0.3%polled, 3 min agoKalshi 1%polled, 1 min agoBest Yes 0.4¢ on Polymarket, $100 pays $25,000 (250x)
Polymarket
Contract
7
Last price
0.3%
As of
Polled 3 min ago
Buy Yes
0.4¢
Sell Yes
0.1¢
$100 on Yes pays
$25,000 (250x)
Volume
$707
Trade this on Polymarket
Kalshi
Contract
Below 7
Last price
1%
As of
Polled 1 min ago
Buy Yes
1¢
Sell Yes
—
$100 on Yes pays
$10,000 (100x)
Volume
$4K
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 0.1¢, at or below the cheapest ask of 1¢.

No cross-venue arbitrage right now: on every matched outcome, the best bid on one venue is at or below the cheapest ask on the other. Find markets with open spreads

Mostly the same bet: two differences

Where they differ

  • Seat counts depend on when races are called; venues use different settlement deadlines for uncalled seats.
  • 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: Pennsylvania Department of State, Associated Press
Show full rule comparison
  • Seat counts depend on when races are called; venues use different settlement deadlines for uncalled seats.
  • 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.

  • 11
  • 10
  • 9

Live prices for 11

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

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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

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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 "How many House seats will the Democrats win in Pennsylvania?". 11 leads at 32.1%. Next is 10 at 27.5%. $90K has traded across 8 outcomes on Kalshi and Polymarket. The market is expected to resolve by Nov 4, 2026.

This market will resolve according to the number of seats in the US House of Representatives won by the Democratic Party in Pennsylvania in the 2026 United States midterm election. All Pennsylvania US House of Representatives elections held as part of the 2026 United States midterm election that elect voting members and determine representation in the upcoming 120th congress are included. Special elections to fill a vacancy for the remainder of an unexpired term are not included, whether or not held concurrently with the 2026 United States midterm election. Runoffs for qualifying elections will determine attribution of the relevant seat. Seats are attributed to the party under which the member was elected. If a member-elect changes party affiliation or vacates their seat after the date of the 2026 United States midterm election, the seat is attributed to the party under which the member was elected. Members of the House elected as independents who formally caucus, or who announce their intent to caucus, with a party prior to the date of the 2026 United States midterm election are included in that party’s count. If the caucus decisions of relevant members of the US House of Representatives elected as independents cannot be determined as of the date of the 2026 United States midterm election, this market may remain open until the earlier of (i) an announcement from the relevant members of their intents to caucus, or (ii) January 4th, 11:59 PM ET of the following calendar year. If no such announcement is made by January 4th, 11:59 PM ET of the following calendar year, the member will not count towards the seat count of any party. The resolution sources for this market will be official information from relevant state electoral authorities, the United States Congress, and a consensus of credible reporting.

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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