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Blue wave in 2026?
polymarket
kalshi

Blue wave in 2026?

Total volume:
$1,142,517
Volume 24h:
$70,843
84%
Liquidity:
$23,018
0.31%
Open interest:
$669,059
11%

Will Democrats hold 218 or more seats in the House AND hold 49 or more seats in the Senate?

all

2 markets

Kalshi

Polymarket

consensus

News

Positive

Negative

Neutral

Hover marker for details

Vol.

·

Resolves Feb 1, 2027

Will Democrats hold 218 or more seats in the House after the 2026 midterms AND hold 49 or more seats in the Senate after the 2026 midterms?

86%chance
Amount

$

Trade on
kalshi

Trade on Kalshi

Join Kalshi and score $25 for your first trade.At 87¢ buys you 115 shares | Odds: 86% Total Payout: $115 | Net Profit: $15 Multiplier: 1.15x | ROI: 15% | APY: 55% 116 days to resolution
You will be redirected to the platform to complete this trade.
Outcome
Trade
Chance %
Price
Spread
Liquidity
Volume
24h
7d
Open Interest
Ends in
Result
kalshi

Will Democrats hold 218 or more seats in the House AND hold 49 or more seats in the Senate?

Trade
86%
Yes 87¢No 14¢
1¢
N/A
$1,062,525
7%
32%
$669,059
3mo 3w 5d
active
polymarket

Blue wave in 2026?

Trade
85%
Yes 85¢No 16¢
1¢
$23,018
$79,992
0%
4%
N/A
2mo 4w
active
PredictionHero
PH Consensus
85.9%
Yes 86¢No 15¢
Avg: 1¢Max: 1¢
Total markets: 2

Intro

This market tracks whether the Democratic Party will control both the House of Representatives and the Senate after the 2026 US midterm elections, requiring at least 218 House seats and 49 Senate seats. Currently, the consensus probability of Democrats achieving this outcome is 86.0%, as aggregated from Polymarket and Kalshi. Resolution will be based on official results from state electoral authorities and the United States Congress. Keep an eye on the results coming out of the November 2026 election, as these will determine the final seat counts and ultimately resolve this market by February 1, 2027.

PredictionHero - Resolution Divergence Alerts (RDA)

Unified Resolution Criteria (Consistent across platforms)

Both Polymarket and Kalshi utilize the same seat count thresholds (218 House, 49 Senate) to determine a 'blue wave' outcome.Primary resolution logic: Official results from state electoral authorities and the United States Congress.

Core resolution logic:

  • Democrats must hold at least 218 seats in the House of Representatives.
  • Democrats must hold at least 49 seats in the Senate.
  • Runoff elections will be included in the seat counts.
  • Independent members who caucus with Democrats will be counted as Democrats.
  • Vacant seats will be attributed to the party of the most recent member.

Edge cases & clarifications:

  • Independent Senators/Representatives: If an independent member caucuses with the Democratic party, they will be counted towards the Democratic seat count. If their caucus affiliation is unclear by January 4th of the following year, they will not be counted.
  • Vacant Seats: Vacant seats will be attributed to the party affiliation of the most recent member to hold that seat as of the election date.
  • Post-Election Party Switching: If a member-elect changes party affiliation after election day but before the formal organization of Congress, the seat is attributed to the party under which the member was elected.
Timing: Resolution will occur after all election results, including any necessary runoffs, are finalized and certified by relevant state and federal authorities, but no later than January 4th of the following calendar year to account for any delayed caucus announcements.Our PredictionHero Resolution Divergence Alerts (RDA) are there to help users identify potential differences across platforms. They do not replace or supersede the official rules and description of any prediction market. Users are solely responsible for reviewing and understanding the applicable rules and resolution criteria before placing any trade or bet. If you notice a potential inconsistency, discrepancy, or error in an alert, please report it to our team so we can review and improve the accuracy of our data.

Polymarket

This market will resolve to “Yes” if both of the following conditions are met as a result of the 2026 midterm elections: - Democrats have a seat count of 218 or more in the House - Democrats have a seat count of 49 or more in the Senate Otherwise, this market will resolve to “No”. The Senate seat count includes all regular and special Senate elections that determine representation in the upcoming 120th Congress and are scheduled to take place in November 2026 as of October 31, 2026. Vacant Senate seats for which no election or special election to fill the seat is scheduled to take place in November 2026 as of October 31, 2026 will be treated as held by the party affiliation of the most recent member to hold that seat. The House seat count includes all House elections in the 2026 United States midterm election that elect voting members and determine representation in the upcoming 120th Congress. Where a Senate or House seat is decided by a runoff, the runoff result will determine attribution of that seat, even if it takes place after November 2026. For seats contested in the specified election, seats are attributed to the party under which the member was elected. If a member-elect changes party affiliation, or vacates their seat, between election day and the formal organization of Congress, the seat is attributed to the party under which the member was elected. For seats not contested in the specified election, seats are attributed to the party that holds the seat as of the date of the election. If a current sitting member of the U.S. Senate who is not up for election changes party affiliation or vacates their seat after the date of the election, the seat is attributed to the party under which the member was affiliated at the time of the election. Senate and House members elected as independents who formally caucus with, or, for newly elected members, who announce their intent to caucus with a party are included in that party’s count. If the caucus decisions of members of the Senate or House elected as independents cannot be determined on the date of the 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.

Kalshi

If ALL of the following occur: Democrats hold 218 or more seats in the House after the 2026 midterms AND Democrats hold 49 or more seats in the Senate after the 2026 midterms, then the market resolves to Yes.

Frequently asked questions

On Polymarket and Kalshi, this dashboard tracks a consensus view of whether a “Blue wave” will occur in the 2026 US elections. Currently, the aggregated volume across both platforms is $1,142,429, with $69,961 traded in the last 24 hours. The current implied probability of this outcome, as reflected by the combined trading activity in the 2026 US election market, is approximately 1.5. This allows traders to see how the collective wisdom of the crowd assesses the likelihood of Democratic gains in both the House and Senate during the midterms. The dashboard provides a unified view of this important political event.

Prediction market odds, like those found in this market, often offer a different perspective than traditional polling averages. While polls capture a snapshot of current sentiment, prediction markets aggregate the wisdom of the crowd, reflecting not just *what* people think, but *what they believe others will do*. This can lead to more accurate forecasts, especially as the election draws nearer and more information becomes available. The current pricing in this market incorporates a wide range of factors beyond simple vote preference, including fundraising, candidate quality, and broader political trends. It’s a dynamic assessment of probabilities, not just a static measure of support.

Polymarket and Kalshi can show different implied probabilities for the same outcome because of liquidity, fee structure, participant mix, and how each venue defines the contract. Prices on Polymarket and Kalshi may differ due to variations in trader demographics, market design, and liquidity. Polymarket currently favors Will Democrats hold 218 or more seats in the House after the 2026 midterms AND hold 49 or more seats in the Senate after the 2026 midterms? at 84.5%, while Kalshi leans toward Will Democrats hold 218 or more seats in the House after the 2026 midterms AND hold 49 or more seats in the Senate after the 2026 midterms? at 86.0%. These discrepancies can also arise from differing levels of information available to traders on each platform, or from strategic trading behavior unique to each venue. Furthermore, the volume traded on each platform – Polymarket has seen volume of approximately $69,776, while Kalshi has volume of around $657,281 – can influence price discovery and create temporary divergences.

This market resolves around Feb 1, 2027, with the outcome confirmed once the event is verifiable from credible public reporting. Specifically, the resolution will be based on whether Democrats achieve a majority in both the House of Representatives and the Senate following the 2026 midterm elections. The final composition of Congress will be verified against credible public sources to determine whether the conditions for a 'Blue wave' have been met. Traders should monitor news and election results as they become available leading up to the resolution date.

Numerous signals and events could significantly impact this market. Major economic shifts, unexpected geopolitical events, and significant changes in candidate performance or fundraising could all influence trader sentiment. Key primary election results, legislative developments impacting voter turnout, and any scandals or controversies involving prominent political figures will be closely watched. Furthermore, shifts in polling data, although not the primary driver of prediction market prices, can still contribute to price movements. Any event that alters perceptions of the Democratic Party's chances of success in the 2026 midterms has the potential to move this market.