U.S. House Majority Leader Eric Cantor of Virginia lost to a tea party challenger on Tuesday in a stunning Republican primary upset that sent shockwaves through Congress and gave the conservative movement a landmark victory.
Cantor, the No. 2 Republican in the House of Representatives, was easily beaten by college economics professor David Brat, who accused Cantor of betraying conservative principles on spending, debt and immigration.
The result could halt efforts to craft a House immigration reform bill, as nervous Republicans hustle to protect themselves against future challenges from the right ahead of the Nov. 4 midterm elections.
It could also make Republicans even more hesitant to cooperate with President Barack Obama and Democrats for fear of being labeled a compromiser.
Cantor had been seen by many as an eventual successor to House Speaker John Boehner, and his defeat will mean a shake-up in the Republican leadership at the end of the year among House members nervous about the depth of public anger toward Congress.
A seven-term congressman with ties to the financial industry, Cantor had spent more than $5 million to head off the challenge from Brat, a political newcomer who teaches at Randolph-Macon College.
Brat spent only about $122,000, according to the Center for Responsive Politics, and was not seen in the media or national Republican circles as a danger to Cantor.
The victory also emboldened conservative leaders, and could encourage a challenge to Boehner when the new leadership team is chosen.
"Eric Cantor's loss tonight is an apocalyptic moment for the GOP establishment. The grassroots is in revolt and marching," said Brent Bozell, a veteran conservative activist and founder of the Media Research Center and ForAmerica.
With nearly all precincts reporting, Brat had about 56 percent of the vote to Cantor's 44 percent.
"I know there are a lot of long faces here tonight," Cantor told supporters. "It's disappointing, sure."
Brat, speaking to an ecstatic crowd, said: "This is the happiest moment, obviously, of my life."
Blow to Republican establishment
The result was a blow to the Republican establishment, which had scored a string of victories over the tea party in primaries to select candidates for the November elections. Republicans are hoping to pick up six seats to gain a Senate majority, but are considered heavy favorites to retain a House majority.
"We all saw how far outside the mainstream this Republican Congress was with Eric Cantor at the helm, now we will see them run further to the far right with the tea party striking fear into the heart of every Republican on the ballot," said Representative Steve Israel of New York, who heads the House Democratic campaign committee.
During the primary campaign, Brat repeatedly accused Cantor of supporting some immigration reform principles, including "amnesty" for undocumented workers. In response, Cantor had sent voters a mailer boasting of his role in trying to kill a House immigration bill that included that provision.
Brat also accused Cantor of losing touch with his central Virginia district while serving the party's leadership.
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Republican strategists suggested Cantor had been too slow to realize how real the threat from Brat was.
"Easiest way to lose a campaign is to not take your opponent seriously," strategist Matt Mackowiak said on Twitter.
Former House Speaker Newt Gingrich said on CNN that Cantor had helped make Brat better known by attacking him by name in the late stages of the campaign.
The result unleashed immediate speculation about a possible replacement for Cantor when the House meets to pick new leaders at the end of the year, including Jim Jordan of Ohio, Jeb Hensarling of Texas and Steve Scalise of Louisiana.
U.S. Senator Lindsey Graham of South Carolina also faced a tea party challenge on Tuesday, but he beat a crowded field of six challengers who also had accused him of not being conservative enough.