Poll shows most likely voters have decided, but 15% remain open to persuasion
A weekly Economist/YouGov poll released on Oct. 16, 2026 found that a clear majority of likely voters say their minds are made up about who they will support in the upcoming midterm elections, but a sizable share remain open to persuasion.
The finding matters because it indicates that, even with strong partisan certainty, campaign messages and outreach could still sway outcomes in closely contested races.
Among respondents in states with Senate races, 78% said their mind was made up. Ten percent said they would consider voting for a different candidate, and another seven percent remained undecided. The poll highlighted Ohio’s tight Senate contest between Sen. Jon Husted (R‑OH) and Democrat Sherrod Brown as an example of where the persuadable segment could be decisive.
In congressional districts, 80% of voters said they had decided, while seven percent said they might consider a different candidate and eight percent remained undecided. Together, the 15% who are not firmly decided could tip the balance in the 21 House toss‑up races identified by the Cook Political Report.
Party breakdown shows that 89% of Democrats, 77% of Republicans and 69% of independents claim their minds are made up. Among independents, however, 11% would consider a different Senate candidate and 12% are undecided; for House races, 8% of independents would consider a different candidate and 15% remain undecided.
When asked about likely control of Congress, 43% of respondents expect Democrats to retain the House versus 30% who expect Republican control. For the Senate, 40% anticipate a Democratic majority, 35% a Republican one, and a quarter are unsure.
The survey was conducted Oct. 10‑12, 2026, with a margin of error of plus or minus 3.5% after weighting. It comes weeks before the Nov. 3 election, as candidates ramp up rallies in key swing states such as Ohio, Alaska, Georgia, Kentucky, Kansas and North Carolina.
With a sizable slice of the electorate still undecided or open to change, campaign teams are likely to focus resources on the persuadable 15% as the election approaches, hoping to turn uncertainty into votes in the nation’s most competitive contests.
