John C. Whitbeck resigned Saturday as chairman of the Republican Party of Virginia, weeks after Corey Stewart won the party’s nomination to take on Sen. Tim Kaine (D) in the November election.

“Other political opportunities have arisen for me that I am thinking about pursuing,” he told members of the party’s governing board at a meeting. He did not elaborate.

Whitbeck has presided over a particularly dismal stretch for Virginia Republicans, who lost all three statewide offices last year and saw their overwhelming majority in the House of Delegates dwindle to the narrowest possible margin.

Virginia is also the only Southern state Donald Trump lost in 2016 presidential election, and the last statewide election Republicans won there was in 2009, when Robert F. McDonnell was elected governor.

Despite electoral losses, fellow Republicans credit Whitbeck with pulling the party out of debt and acting as a stabilizing force after a succession of chairmen came and went during the 2000s.

There is speculation Whitbeck does not want to spend the next four months answering for Stewart, who is known for provocative campaign antics and likes to say he was “Trump before Trump was Trump.”

Stewart, who narrowly lost the GOP nomination for governor in June after attacking illegal immigration and calling for protection of what he called “Confederate heritage,” has promised a “ruthless” and “vicious” campaign against Kaine.

A recent Quinnipiac University survey found that Kaine leads Stewart by 18 points, with 54 percent of voters supporting the Democrat while 36 percent backed Stewart.

Asked last week by The Washington Post if he would vote for Stewart, Whitbeck said, “The party supports all nominees.”

In the days after Stewart’s primary win, two party leaders resigned, but neither would say why.

Kevin Gentry, the vice president for special projects and development at Koch Industries, left his position on the executive committee of the party’s governing board, and Davis C. Rennolds stepped down as chair of the Richmond GOP.

Gentry emailed his resignation to the party shortly before 7 a.m. the morning after the primary. “I served since 1992, and it’s time for some new blood and new perspectives,” he said in an interview.

The Koch-funded group Americans for Prosperity has said it will not support Stewart’s campaign.

Rep. Barbara Comstock, who is in a tough fight for re-election from norther Virginia and is considered one of the most endangered Republicans in Congress, said she appreciated Whitbeck’s tenure.

“As the only woman in the entire Virginia congressional delegation, I thank John, the father of three daughters, for his help in my elections and for being a fighter for more women and diversity in our party,” Comstock said in a statement.

Whitbeck took over as chairman, an unpaid position, in January 2015, when the party was in financial debt and deeply divided over Dave Brat’s defeat of then-House Majority Leader Eric Cantor.

The chairman is the symbolic head of the party and responsible for fundraising — which suffered after Cantor’s loss — as well as hiring the organization’s staff.

Whitbeck brought in his friend and former campaign manager, John Findlay, to serve as executive director.

A 42-year-old lawyer in private practice, Whitbeck is a California native and lives in Leesburg. He teaches at his alma mater, George Mason University Law School, according to the bio on his law firm website.

Whitbeck ran unsuccessfully for the House of Delegates in 2011 and lost a January 2014 special election for the state Senate to replace Democrat Mark Herring when he became attorney general.

He courted controversy in 2013 for telling an anti-Semitic joke at a rally for then-Attorney General Ken Cuccinelli II, who was running for governor at the time. Whitbeck initially defended the remark but later apologized.

He was previously chairman of the 10th Congressional District Republican Committee and helped that district’s congresswoman, Barbara Comstock, win her first term.