Rep. Eric Cantor is expected to resign his post as House majority leader effective July 31, GOP officials said.
The officials spoke on condition of anonymity, saying they were not authorized to pre-empt an official announcement.
The news comes one day after the Virginia lawmaker lost his primary bid against a Tea Party favorite.
Everyone expected the second most powerful man in the U.S. House of Representatives to win easily his re-election bid in Virginia's Republican Party primary. After all, Cantor outspent his opponent more than 20-1.
But when all the votes were counted, Tea Party-backed candidate David Brat came out on top.
"The reason we won this campaign, if there's just one reason, that's because dollars do not vote, you do," Brat said in his Tuesday night victory speech.
Luke Russert, a political correspondent for NBC News, offered more insight on Tuesday's primary upset on The 700 Club, June 11.
Cantor, meanwhile, conceded his loss, telling his supporters, "Obviously, we came up short."
"I know there's a lot of long faces here tonight. It's disappointing, sure," he said.
Now the question is what led to Cantor's downfall and how will the Republican Party react?
"This was a smack down. This was voters less than two hours from Washington, D.C., saying we don't like the direction the country is headed and we don't like the Republican leadership's response to it," CBN Sr. Political Editor John Waage said.
In his concession speech Tuesday night, Cantor described himself as a conservative.
"We want to focus our efforts as conservatives, as Republicans, on putting forth our conservative solutions so that they can help solve the problems for so many working middle class families," Cantor said.
But Virginia voters didn't buy it. Tea Party members and other conservatives viewed Cantor as the ultimate insider, close to Wall Street, an establishment Republican.
On the other hand, Brat, an economics professor from Randolph-Macon College in Ashland, Virginia, capitalized on conservative dissatisfaction with Cantor and ran his race as an anti-establishment candidate.
"The basic premise is power belongs to the people and that's what we're gonna do," Brat said.
While Brat's win represents an amazing comeback victory for the Tea Party, it's unclear at this time what impact it will have on the Republican Party and on congressional campaigns this fall.
"Essentially Cantor got clobbered by a political novice who had a fraction of his money to spend," Waage said. "And that ought to send a message to the leadership in both parties, but I'm not sure it will."
Two main issues dominated his winning campaign against Cantor: the massive budget deficit and immigration reform. Brat accused the House majority leader of wanting to give citizenship papers to illegal immigrants.
However, it wasn't all bad news Tuesday for establishment Republicans.
Sen. Lindsey Graham, one of the most prominent Republicans in the Senate, handily won his primary bid in South Carolina Tuesday. Graham avoided a runoff by gaining 59 percent of the vote.
Tea Party members also said Graham was not a true conservative, especially on immigration. Graham had made that a top campaign issue. He was also critical of President Barack Obama's foreign policy.
"One thing I learned tonight is that we're not a bunch of isolationists in South Carolina," Graham said. "We believe in peace through strength and when it comes to radical Islam, we're gonna fight you over there so you don't come here."
Now political observers wonder whether party leaders will advance a conservative agenda in the fall campaign or present themselves as moderates in hopes of defeating Democrats.