OKLAHOMA CITY (AP) -- Republican Sen. Jim Inhofe plans to announce soon that he will retire from Congress before his six-year term is up, triggering a special election this year in Oklahoma to pick his replacement, according to a person with direct knowledge of the senator's plans.
Inhofe, 87, is expected to serve until the current session of Congress ends in January, the person said. He was elected to a fifth Senate term in 2020. The person spoke to The Associated Press on the condition of anonymity to discuss sensitive details.
The timing of the announcement is related to a quirk in Oklahoma law that requires the governor to call a special election if a lawmaker announces they intend to retire before March 1. The special election would be held concurrently with the statewide primary, runoff and general election. Inhofe's chief of staff is expected to run for the Senate seat and Inhofe is expected to support his candidacy, the person said.
Republicans will be heavily favored to retain the seat, as Oklahoma hasn't sent a Democrat to the Senate since 1990.
Inhofe's announcement is likely to trigger a series of announcements from Republicans planning to run for the seat. Among those expected to consider the race are Republican U.S. Reps. Kevin Hern and Markwayne Mullin, former Speaker of the Oklahoma House of Representatives T.W. Shannon, who ran for U.S. Senate in 2014, and Tulsa attorney Gentner Drummond, who is currently running for attorney general. Oklahoma's three-day filing period begins April 13.
"This is going to be the most substantial shakeup in Oklahoma politics since at least 1994," said Pat McFerron, a Republican pollster and consultant in Oklahoma City. That year, Inhofe won the U.S. Senate seat in a special election and Republicans captured three U.S. House seats.
A longtime fixture in Oklahoma politics, Inhofe is the ranking Republican on the Senate Armed Services Committee. He first won the Senate seat in a special election in 1994 after then-Democratic Sen. David Boren stepped down to become president of the University of Oklahoma. Before that, Inhofe served in the Oklahoma House, Oklahoma Senate and three terms as Tulsa's mayor before winning a seat in the U.S. House.
"There's been nobody who's done more to protect and promote Oklahoma's infrastructure, particularly military infrastructure, than Jim Inhofe," McFerron said. "He's been a vital part of Oklahoma's federal delegation for my entire adult life and a seminal figure in Oklahoma politics."
Inhofe, a staunch conservative, has long dismissed global warming as a hoax and famously tossed a snowball on the Senate floor during a Washington snowstorm to prove his point.
Even so, as longtime chairman of the Senate Environment and Public Works Committee, he worked closely with liberal Sen. Barbara Boxer, D-Calif., to enact a number of environmental laws, including a sweeping 2016 law to impose new regulations on tens of thousands of toxic chemicals in products such as household cleaners, clothing and furniture.
Inhofe was a strong backer of former President Donald Trump, who praised him for his "incredible support of our #MAGA agenda" while endorsing the senator's 2020 reelection bid. Inhofe won re-election that year with nearly 63% of the vote in a five-candidate race.
In 2021, Inhofe defied some in his party by voting to certify Democrat Joe Biden's victory in the presidential election, saying that to do otherwise would be a violation of his oath of office to support and defend the Constitution. He voted against convicting Trump at both of his impeachment trials.
The senator's office did not immediately return a request for comment.