By Illinois Review
A new survey of likely Republican primary voters shows former state Sen. Darren Bailey expanding his lead in the 2026 Illinois Republican primary for governor, reinforcing findings from an earlier major poll released by WGN-TV.
The latest poll, conducted by Osage Research, finds Bailey supported by 57 percent of likely Republican primary voters. Businessman Ted Dabrowski registered at 8 percent, Rick Heidner at 9 percent, and DuPage County Sheriff James Mendrick at 4 percent. Another 23 percent of respondents remain undecided.
Bailey’s margin represents a 49-point advantage over his nearest competitor and exceeds the combined support of the rest of the field.
The Osage Research findings follow the first major public poll of the race, commissioned by WGN-TV and conducted by Emerson College Polling in early January. That survey showed Bailey leading with 34.4 percent, compared with Dabrowski at 8.2 percent, Mendrick at 5.4 percent, and Heidner at 1.1 percent, with 46.4 percent undecided.
Taken together, the two polls suggest a consistent pattern: Bailey has maintained a substantial lead over the field while increasing his share of committed support as undecided voters shrink.
While the polls were conducted by different firms using different methodologies, both show Dabrowski and other challengers stuck in single digits and unable to close the gap.
The Osage Research survey also measured favorability, finding Bailey with a 59 percent favorable rating among likely Republican primary voters. According to the firm, Bailey’s support is broadly distributed across the Republican electorate rather than concentrated in a single region or demographic group.
By comparison, the WGN–Emerson poll earlier this year found nearly half of voters undecided, reflecting an electorate still forming opinions at an early stage. The Osage Research results indicate that a significant portion of those voters have since moved into Bailey’s column rather than toward other candidates.
Political analysts often look for movement between early polls to assess whether a race is consolidating or fragmenting. In this case, both surveys point in the same direction: Bailey leading decisively, with no clear alternative coalition emerging among the remaining candidates.
The Osage Research poll was conducted among 412 likely Republican primary voters statewide using a mix of live phone interviews and text-to-web responses. The margin of error is ±5.66 percent, with quotas set for age, gender, and geography to reflect the anticipated 2026 Republican primary electorate.
The Illinois Republican primary for governor is scheduled for March 17, 2026.
