Representative Bob Gibbs of Ohio announced on Wednesday that he would not seek re-election, just as early voting got underway in the state. Ohio’s redistricting process had forced Mr. Gibbs, who has served in Congress since 2011, into a Republican primary against a Trump-backed challenger, Max Miller, among others.
Mr. Gibbs said in a statement that the tumultuous effort to redraw the state’s congressional map had become a “circus,” and he criticized the last-minute changes to his rural district south of Cleveland.
“It is irresponsible to effectively confirm the congressional map for this election cycle seven days before voting begins, especially in the Seventh Congressional District where almost 90 percent of the electorate is new,” he said.
Mr. Gibbs’s name will still appear on the ballot in the district but signs will be posted at voting locations stating that votes for him will not be counted, said Rob Nichols, a spokesman for the Ohio Secretary of State, in a brief interview.
Mr. Gibbs was facing a serious primary challenge from Mr. Miller, an aide to former President Donald J. Trump. Mr. Trump endorsed Mr. Miller last year when the Ohio candidate was aiming to unseat Representative Anthony Gonzalez, who had voted to impeach Mr. Trump. But Mr. Gonzalez said in September that he would not run for re-election.
Mr. Gibbs and Mr. Gonzalez were later drawn into the new Seventh District. Mr. Gibbs voted against impeaching Mr. Trump after the Capitol riot and voted to overturn the results of the presidential election, positions that the former president has treated as litmus tests for which Republicans he will support in 2022.
Mr. Miller on Wednesday praised Mr. Gibbs’s tenure.
Ohio is losing one of its 16 congressional seats as part of the once-a-decade redistricting process after the latest census. The state’s efforts to redraw its district lines have been mired in legal challenges.
In January, the Ohio Supreme Court rejected a congressional map drawn by the state’s Republican-dominated Redistricting Commission, calling it too partisan for a state where the G.O.P. has lately won about 55 percent of the statewide popular vote.
The court is planning to hold a hearing on the new congressional map sometime after the May 3 primary, and is hearing challenges to a fourth set of state legislative maps. Frank LaRose, Ohio’s Secretary of State, removed the state legislative races from the May 3 ballot and a new date for those elections has not been set.
Jen Miller, the executive director of the League of Women Voters of Ohio, echoed Mr. Gibbs’s frustration with redistricting. “Ohio is swingable but it doesn’t seem that way because we have this history of extreme gerrymandering,” she said.
Redistricting is a potentially decisive factor in determining which party will control Congress. Both parties have sought to give themselves advantages in states across the country — giving rise to legal wrangling in several states, including New York, Maryland, Alabama and North Carolina.
Michael Wines contributed reporting.