Green Party Removal Fails to Lift PA-07 GOP Odds, Now at 20%

---

Republican Chances in PA-07 House Race Fall to 20% Despite Ballot Removal That Should Help the GOP

Republican incumbent Ryan Mackenzie's implied probability of winning the PA-07 House race has dropped to 20% on prediction markets, down 9 percentage points in three days, even after a Pennsylvania court removed Green Party candidate Andrew Tupone from the ballot on September 9. That removal eliminated what conventional wisdom treats as a left-leaning vote splitter. At the same time, the Democratic primary field has fragmented, with multiple candidates competing for the nomination against Bob Brooks. On paper, both developments should improve Ryan Mackenzie's position.

The prediction markets read it differently. Bettors appear to treat Tupone's removal as a net negative for Mackenzie: without a Green Party option absorbing protest votes, the anti-incumbent electorate consolidates behind whichever Democrat emerges. The fragmented primary, rather than weakening the eventual nominee, may be generating attention and fundraising energy across the Democratic field.

---

Live PA-07 House Winner Odds: Where the Market Stands Today

Prediction-market view

Live prices, venue by venue

Compare the latest YES price at each venue. Check market rules, liquidity, and fees before trading.

Bob Brooks (D)

Consensus YES price across 4 venues

81%average

Polymarket USBest YES price81¢Polymarket82¢Kalshi83¢PredictIt88¢

Ryan Mackenzie (R)

Consensus YES price across 4 venues

19%average

PolymarketBest YES price17¢Kalshi18¢Polymarket US20¢PredictIt29¢

Current new-user offer · Polymarket US

Deposit $10, get $50Code PRED

New users only. Eligibility restrictions and terms apply.

View current offer

The Republican Party sits at 20% across aggregated platforms, with the Democratic Party priced as a heavy favorite. Platform-level prices show a notable spread: Kalshi and Polymarket both list Republicans at 25%, while PredictIt prices the GOP at 11%. That 14-percentage-point gap between PredictIt and the other two venues is unusually wide for a House race and points to structural differences in how each platform's participant base evaluates this district.

PredictIt's lower Republican price may reflect its user base of political hobbyists who weight district-level fundamentals (Biden carried the redrawn PA-07 by a comfortable margin in 2020). Kalshi and Polymarket, which attract more financial-markets crossover traders, may be pricing in a slightly higher chance of a late GOP recovery or a messy Democratic primary outcome. Either way, no venue gives Mackenzie better than a one-in-four shot.

---

PA-07 Republican Price History: When Did Ryan Mackenzie's Odds Start Falling?

The three-day chart complicates the ballot-removal narrative. If the drop preceded the September 9 court ruling, bettors were already repricing Mackenzie lower on other information, and the Tupone removal simply failed to arrest the slide. If the drop accelerated after the ruling, the market interpreted the removal as net-negative for the GOP.

Outside spending may be part of the picture. J Street's super PAC announced $3 million in spending targeting AIPAC-backed Republicans in swing districts, a category that could include PA-07. The timing aligns with the market move and would explain why bettors discounted Republican chances even as structural ballot dynamics shifted.

---

Are There Polls for the PA-07 House Race in 2026?

Public polling for individual House districts remains scarce in September of a midterm cycle, and PA-07 is no exception. No high-quality independent survey testing Mackenzie against Brooks or any other Democratic contender head-to-head has appeared publicly. That absence leaves the prediction market as the primary real-time gauge of this race's competitiveness.

Without polling, bettors are likely relying on district-level partisanship scores, fundraising reports, and national environment indicators. PA-07 leans Democratic in presidential elections, and the broader trend of 2018-era swing-district incumbents facing tougher reelection fights adds context. Mackenzie, who flipped the seat in a favorable Republican cycle, now faces the structural headwind of defending it in a midterm where the president's party historically loses ground.

---

The Case for Republicans Being Underpriced at 20%

The strongest argument that bettors are too bearish on Mackenzie centers on the Democratic primary. A fractured field running through a bruising nomination fight could leave the eventual Democratic nominee financially depleted, ideologically pinned to positions unpopular in the district's moderate suburbs, and facing a unified Republican incumbent who spent the primary season stockpiling cash.

Mackenzie also benefits from incumbency advantages that prediction markets sometimes underweight in House races: constituent service name recognition, franking privileges, and the ability to localize messaging away from national headwinds. If the Democratic primary turns negative, or if the eventual nominee is a weaker general-election candidate than Brooks, a 20% price could look cheap in retrospect.

---

What Happens Next for PA-07 Bettors

The current 20% price implies the market sees roughly a four-in-five chance that Democrats flip this seat. For that to hold, the Democratic primary needs to produce a credible nominee who can consolidate the party's base and the newly available Green Party voters. Any polling showing Mackenzie within single digits would likely trigger a repricing upward.

For the latest movement across the full field, check the PA-07 House winner odds hub. The November 4, 2026 resolution date leaves seven weeks for campaigning, outside spending, and late-breaking polls to test whether 20% is a fair price or a market overreaction driven by thin information and national mood.