Polymarket
KalshiIllinois's 4th District: A Disputed Handoff Still Prices as a Safe Democratic Seat
The Illinois 4th District odds 2026 board prices an open Chicago seat as a Democratic hold even though its nominee reached the ballot through a last-minute filing switch, because the market rests on the district's lopsided record and on a field that splits the opposition three ways. Patty Garcia, the Democrat, faces Republican Lupe Castillo, Working Class Party candidate Ed Hershey and independent Chris Getty, the mayor of Lyons, on November 3, 2026. The live board above carries Kalshi's and Polymarket's current prices for the two major parties.
How the Illinois 4th District Seat Opened
The Clerk of the House member list, published October 1, 2026, records Jesús G. "Chuy" García, of Chicago, as the Democratic member for the 4th District. He is not on the November ballot. The Chicago Sun-Times reported on October 1, 2026 that García filed petitions to run for re-election on October 27, 2025, that his chief of staff, Patty Garcia, filed her own petitions just before the 5 p.m. deadline on November 3, 2025, and that García later withdrew his. The State Board of Elections' candidate list shows Patty Garcia's Democratic filing time as 5:00 p.m. on November 3, 2025.
That sequence left her as the only Democrat on the March 17, 2026 primary ballot, and she took 52,616 votes unopposed. The Sun-Times reports that she is no relation to the congressman, holds a Ph.D. in education policy, worked in his office from 2019 and resigned as his chief of staff in November 2025. The paper reports that critics panned the switch as a coronation, and that it has drawn much of the attention in a race whose general elections have not been close.
Who Else Is on the Illinois 4th District Ballot
The State Board of Elections' list, as of October 16, 2026, shows four candidates still standing: Garcia for the Democrats, Lupe Castillo for the Republicans, Ed Hershey for the Working Class Party and Chris Getty as an independent. Two other independent filings, by Mayra Macias and Byron Sigcho Lopez, were removed from the list on July 21, 2026, which the Sun-Times attributes to their not submitting enough valid signatures.
Castillo was the Republican nominee in 2024 and was unopposed in the March 17, 2026 Republican primary with 8,336 votes; the Sun-Times quotes her platform as "pro-family values and policies." Hershey, a teacher at Lindblom Math and Science Academy for 16 years, has been the Working Class Party's candidate in the last two elections. Getty, the Sun-Times reports, has been mayor of Lyons since 2009 and is the Lyons Township supervisor; he lists the cost of living, immigration, public safety and government accountability as his priorities.
Why the Illinois 4th District Price Holds Near the Top
What the price is saying is that the 4th's results are so one-sided that a contested nomination does not move them. The Clerk of the House's statistics for the November 5, 2024 election show García with 139,343 votes, Castillo with 56,323 and Hershey with 10,704, out of 206,396 cast. In 2022 the State Board of Elections' totals had García at 91,036 votes to 37,352 for Republican James Falakos, with Hershey at 4,605. The Democrat won more than two votes for every one cast for anyone else in both years.
On October 16, 2026, Kalshi had the Democratic contract at 96%, matching Polymarket, and Kalshi's 3% was the cheapest Republican Yes, against Polymarket's 4%. That means the venues treat a Republican win as remote, which fits a party that took 56,323 votes here in 2024 against the Democrat's 139,343.
The board is also the most heavily traded of the Illinois House boards with a Democratic favorite, on Kalshi and on Polymarket. It carried about $62K in lifetime volume on Polymarket as of October 16, 2026, about $46K of it on the Democratic contract, and Kalshi had matched about 12,500 contracts, about 7,100 of them on the Democratic side, which means traders have put real money behind the hold rather than only taking small positions on the long shot.
The Case Against the Illinois 4th District Read
The strongest case against the read is that the threat to a Democratic hold here was never the Republican; it is an independent who can draw Democratic voters unhappy with how the nomination was handed over. Getty is an elected mayor inside the district, and the filing switch gives him an issue no previous challenger had. A reader who holds the counterread would say the 2022 and 2024 results measure a Democrat against a Republican, and this year's question is different.
The rules make that case sharper. Kalshi's Democratic contract pays only if the member sworn in belongs to the Democratic Party, so a Getty win would settle both of its party contracts at No. Polymarket's rules treat a winner without a major-party label as a member of whichever party he most recently said he would caucus with, so the same result could settle differently there. The party contracts price the chance that the seat stays Democratic, not only the chance that Castillo loses.
The price's answer is the size of the hill. García's 2024 total was more than twice the Republican's and more than thirteen times Hershey's, and Getty's line on the ballot carries no party label. An independent who wins here needs to take a large share of voters who have backed the Democratic nominee by wide margins, without a party line on the ballot.
What Changes the Illinois 4th District Read
The read would be wrong if Getty or Castillo shows strength that the past results do not capture. The dated checks:
• Independent polling: Any public survey of the four-way race before November 3, 2026. A poll with Getty in second place, close to Garcia, would be the clearest sign the party contracts are mispricing the independent.
• Ballot finality: October 19, 2026 is the last day a vacancy in nomination can occur and be filled for this election, so the four names on the list are effectively the ballot.
• Early voting: Early voting at permanent polling places opens October 19, 2026.
• Mail ballots: Applications by mail must be received by October 29, 2026, and ballots postmarked by Election Day count if they arrive within 14 days.
• The canvass: Election authorities finish their canvass by November 24, and the State Board of Elections proclaims the results by December 4, 2026.
When the Illinois 4th District Market Resolves
On Kalshi, which lists the race as KXHOUSERACE-IL04-26, the Democratic contract resolves Yes if the House member sworn in for IL-04 for the term beginning in 2027 is a member of the Democratic Party, the Republican contract on the same test; the expected settlement is January 4, 2027, and a consensus media projection can bring it forward. Polymarket resolves on the party of the winning candidate as a consensus of credible reporting indicates, determines the party of a winner without a ballot-listed major-party affiliation by the party that candidate most recently said they would caucus with, and falls back on the Federal Election Commission's official results if there is ambiguity.
Related Illinois Markets
The 4th shares the ballot with the statewide Illinois governor odds and Illinois Senate odds races. Two other Illinois House seats are open this year: the Illinois 8th District odds and the Illinois 2nd District odds. The incumbents' races on the Illinois 11th District odds and Illinois 17th District odds pages round out the closest-priced House boards, and the Illinois elections page lists the full ballot.
