U.S. Sen. Pat Toomey has decided not to run for reelection or for governor of Pennsylvania in 2022, according to two people familiar with his plans, a surprise decision by the Republican with significant implications for the state’s next elections.

» UPDATE: Pat Toomey announces he will not run for reelection to Senate or for Pa. governor in 2022

He is planning to serve out his current Senate term but won’t run for either of those offices, seemingly ending his career in elected office, at least for now. A formal announcement is expected Monday.

Toomey’s office on Sunday neither confirmed nor denied the senator’s plans. The people familiar with his plans spoke on condition of anonymity because they weren’t authorized to discuss the matter publicly.

As the only Republican holding statewide office other than judges, Toomey was widely seen as the likely Republican favorite for governor in 2022. His decision not to run for that office or for Senate could create two wide-open contests on the Republican side, while depriving the party of running its most established current political figure in Pennsylvania.

It will also open a prime Senate target for national Democrats, regardless of who controls the chamber after this year’s election. A large number of current and former members of Congress, state lawmakers, and other local elected officials in both parties are likely to begin jockeying for position in both races.

Most political insiders had expected that Toomey, 58, would wait until after the 2020 election to decide his future. It was not immediately clear why he had decided to make an announcement now, weeks before the Nov. 3 presidential election.

Toomey’s surprise decision comes at an already tumultuous and perilous time for Republicans in Washington. President Donald Trump is hospitalized with the coronavirus. Three GOP senators have also contracted the virus, which could hamper the party’s push to install Judge Amy Coney Barrett on the Supreme Court. And Trump and fellow Republicans face increasingly dire poll numbers, threatening their hold on both the White House and Senate.

“It’s incredibly surprising,” said Charlie Gerow, a Republican consultant in Harrisburg. “It throws dozens of wild cards into the mix.”

The coming Republican primaries for governor and senate will “be a free for all,” Gerow said, with “dozens of candidates emerging from the political and business communities. Half the legislature’s going to want to run.”

Toomey’s absence from the ballot in 2022 could also create an easier path for Democrats hoping to hold the governor’s office and flip his competitive Senate seat. Toomey has won his two Senate elections by the slimmest of margins, but is experienced in statewide races and is a savvy campaigner with significant cash in his campaign account.

However, since his 2016 election he has also become a lightning rod for liberals who have criticized him for, in their view, not standing up strongly enough to Trump. Since that year, protesters have regularly held events outside his offices. If Toomey had run again, he would almost certainly have drawn far more vehement opposition than he has faced in either of his previous statewide campaigns.

Toomey’s decision not to run for Senate isn’t entirely surprising. He has long supported term limits and before his 2016 reelection campaign said it was “likely” to be his last Senate bid.

Toomey also has fulfilled some longtime goals during the Trump presidency, including playing a major role in writing the 2017 bill that cut taxes and rewrote key pieces of the tax code. Earlier this year, he helped craft major provisions in Congress' coronavirus rescue package.

Still, he was seen as a potential gubernatorial candidate and had made several moves that fueled speculation he would run, including playing an unusually vocal role in critiquing Gov. Tom Wolf’s coronavirus response — a relatively rare foray into a state-government issue. He also helped raise money for Heather Heidelbaugh, the Republican running against Attorney General Josh Shapiro. Shapiro is seen as a likely Democratic candidate for governor, so bruising him could have helped Toomey in a potential 2022 match up.

That’s now off the table, leaving no clear Republican favorite for either the senate or gubernatorial races in 2022. If Toomey were to leave office early, Wolf, a Democrat, could appoint his replacement, likely altering the narrow political balance in the chamber.

Charlie Dent, the former Republican congressman from Allentown, met Toomey when the senator moved to the city in the early 1990s and opened a sports bar, Rookies. He helped Toomey run for a seat on the city’s charter study commission, which studied local tax laws and other issues.

Dent said Toomey was always “serious and thoughtful” about issues, but not someone who enjoyed the “glad-handing” side of politics.

“Pat wasn’t one who was thrilled with the politicking and politics that goes with the job. He was always more cerebral, thoughtful, policy-driven,” Dent said Sunday. “You start talking tax reform and he’d salivate.”

Tuesdays With Toomey, which organizes protests against him every week, said Sunday on Twitter that Toomey’s “history of ignoring his constituents and breaking his promises means it is past time for him to leave.”

“I think he would do better in a line of work that doesn’t involve him listening and respecting his constituents, because he did not seem to be able to do that,” Vashti Bandy, one of the leaders of Tuesdays With Toomey, said in an interview.

“We’re not going away,” she added. “We still have two more years with him, so he still has two more years with us.”

A businessman who got his start on Wall Street, Toomey has been a staunch fiscal conservative who focused squarely on economic policy while usually leaving cultural battles aside. He did, however, take on a central role in the national debate on gun laws after the 2012 school shooting in Newtown, Conn., becoming one of the few elected Republicans in the country to come out in support of some tougher gun laws.

Toomey wrote a bipartisan bill with Sen. Joe Manchin (D., W.Va.) to expand background checks to cover more purchases, breaking with many in his party — though the bill failed in a contentious 2013 vote. After that, Toomey became a go-to figure whenever the gun debate arose, but he was unable to make progress advancing the bill, especially as the Senate added more Republicans.

He had long signaled discomfort with Trump, refusing to say whether he would vote for his party’s nominee for president until hours before polls closed in 2016. In the end, he voted for Trump. He has also at times criticized the president’s behavior and rhetoric.

But he has largely backed Trump’s agenda and appointments, and has supported his party’s push to quickly fill a Supreme Court vacancy before Election Day. That was a reversal of the position he took in 2016, when he cited an election eight months away in opposing a confirmation vote for President Barack Obama’s nomination of Judge Merrick Garland to the high court. Republicans now argue this opening is different because the same party now controls the White House and Senate.

There was no indication that his announcement would affect his Supreme Court vote.

Toomey, of the Allentown area, was elected to the U.S. House in 1998 and served three terms. He ran an unsuccessful Senate primary against then-Republican Sen. Arlen Specter in 2004, led the free-market conservative group the Club for Growth, and then in 2010 returned to challenge Specter again. Specter, rather than face the challenge from the right, switched parties. Specter lost the Democratic primary to then U.S.-Rep Joe Sestak, and Toomey beat Sestak in the general election to win the Senate seat.

Staff writer Catherine Dunn contributed to this article