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icon for Massachusetts Senate Election Winner
Politics·US Election

Massachusetts Senate Election Winner

icon for Massachusetts Senate Election Winner
Politics·US Election

Massachusetts Senate Election Winner

Polymarket

$48,024 Vol.

Polymarket

$48,024 Vol.

icon for Ed Markey (D)

Ed Markey (D)

$35,054 Vol.

97%

icon for John Deaton (R)

John Deaton (R)

$12,970 Vol.

3%

This market will resolve according to the winner of the 2026 midterm Massachusetts U.S. Senate election, inclusive of any run-offs. A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date. Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party. The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.Incumbent Democrat Ed Markey holds a commanding position in the 2026 Massachusetts Senate race after decisively winning his September 1 primary against Rep. Seth Moulton by roughly 30 points. The state's consistent Democratic tilt, reflected in recent presidential margins and a partisan voting index exceeding D+14, underpins trader consensus reflected in the 97% implied probability. Polling averages show Markey ahead of Republican nominee John Deaton by 20 points or more, consistent with historical patterns for Democratic Senate candidates in the commonwealth. Deaton's unopposed primary win provides limited momentum against these fundamentals. Late developments such as a major scandal, health event affecting the incumbent, or an unprecedented national Republican surge would be required to meaningfully shift the outcome before November 3.

This market will resolve according to the winner of the 2026 midterm Massachusetts U.S. Senate election, inclusive of any run-offs.

A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date.

Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party.

The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.This market will resolve according to the winner of the 2026 midterm Massachusetts U.S. Senate election, inclusive of any run-offs. A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date. Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party. The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.
Volume
$48,024
End Date
Nov 3, 2026
Market Opened
Oct 13, 2025, 5:07 PM ET

Resolver

0x2F5e3684c...
This market will resolve according to the winner of the 2026 midterm Massachusetts U.S. Senate election, inclusive of any run-offs. A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date. Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party. The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.Incumbent Democrat Ed Markey holds a commanding position in the 2026 Massachusetts Senate race after decisively winning his September 1 primary against Rep. Seth Moulton by roughly 30 points. The state's consistent Democratic tilt, reflected in recent presidential margins and a partisan voting index exceeding D+14, underpins trader consensus reflected in the 97% implied probability. Polling averages show Markey ahead of Republican nominee John Deaton by 20 points or more, consistent with historical patterns for Democratic Senate candidates in the commonwealth. Deaton's unopposed primary win provides limited momentum against these fundamentals. Late developments such as a major scandal, health event affecting the incumbent, or an unprecedented national Republican surge would be required to meaningfully shift the outcome before November 3.

This market will resolve according to the winner of the 2026 midterm Massachusetts U.S. Senate election, inclusive of any run-offs.

A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date.

Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party.

The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.This market will resolve according to the winner of the 2026 midterm Massachusetts U.S. Senate election, inclusive of any run-offs. A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Candidates other than the Democratic or Republican nominee (e.g., Greens, Libertarian, independent) may be added at a later date. Candidates who run as independents will not be encompassed by the “Democrat” or “Republican” options regardless of any affiliation they may have with the party. The resolution source for this market is the Associated Press, Fox News, and NBC. This market will resolve once all three sources call the race for the same candidate. If all three sources haven’t called the race in this state for the same candidate, this market will resolve based on the official certification.
Volume
$48,024
End Date
Nov 3, 2026
Market Opened
Oct 13, 2025, 5:07 PM ET

Resolver

0x2F5e3684c...

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Frequently Asked Questions

"Massachusetts Senate Election Winner" is a prediction market on Polymarket with 2 possible outcomes where traders buy and sell shares based on what they believe will happen. The current leading outcome is "Ed Markey (D)" at 97%, followed by "John Deaton (R)" at 3%. Prices reflect real-time crowd-sourced probabilities. For example, a share priced at 97¢ implies that the market collectively assigns a 97% chance to that outcome. These odds shift continuously as traders react to new developments and information. Shares in the correct outcome are redeemable for $1 each upon market resolution.

As of today, "Massachusetts Senate Election Winner" has generated $48K in total trading volume since the market launched on Oct 13, 2025. This level of trading activity reflects strong engagement from the Polymarket community and helps ensure that the current odds are informed by a deep pool of market participants. You can track live price movements and trade on any outcome directly on this page.

To trade on "Massachusetts Senate Election Winner," browse the 2 available outcomes listed on this page. Each outcome displays a current price representing the market's implied probability. To take a position, select the outcome you believe is most likely, choose "Yes" to trade in favor of it or "No" to trade against it, enter your amount, and click "Trade." If your chosen outcome is correct when the market resolves, your "Yes" shares pay out $1 each. If it's incorrect, they pay out $0. You can also sell your shares at any time before resolution if you want to lock in a profit or cut a loss.

The current frontrunner for "Massachusetts Senate Election Winner" is "Ed Markey (D)" at 97%, meaning the market assigns a 97% chance to that outcome. The next closest outcome is "John Deaton (R)" at 3%. These odds update in real-time as traders buy and sell shares, so they reflect the latest collective view of what's most likely to happen. Check back frequently or bookmark this page to follow how the odds shift as new information emerges.

The resolution rules for "Massachusetts Senate Election Winner" define exactly what needs to happen for each outcome to be declared a winner — including the official data sources used to determine the result. You can review the complete resolution criteria in the "Rules" section on this page above the comments. We recommend reading the rules carefully before trading, as they specify the precise conditions, edge cases, and sources that govern how this market is settled.