How Eric Cantor's Shocking Loss Changes Everything

What happened in Virginia's 7th Congressional District Tuesday night amounted to a political earthquake, with shockwaves that will be felt across the national political landscape.

House Majority Leader Eric Cantor, R-Va., fell to conservative challenger Dave Brat - and not just by a little. Brat's margin of victory was more than 10 percentage points, 44 percent for Cantor compared to 55 percent for Brat, according to the Associated Press.

Analysis: Immigration Issue May Have Felled Cantor

VIDEO: Eric Cantor Loses Primary in Shocking Upset

Why Cantor Got Canned

The implications of Cantor's primary defeat are vast. Here are a few:

IMMIGRATION REFORM IS DEAD

The issue that got Brat going in his primary win was immigration, portraying Cantor as a proponent of "amnesty," which is a stretch even in the bounds of political rhetoric. Cantor's loss effectively eliminates any slim chance the U.S. House of Representatives had of passing immigration reform along the lines of the Senate bill this year. House Speaker John Boehner, R-Ohio, will face even more - and now, likely overwhelming - pressure to shelve these efforts, given the message that just got delivered to his top lieutenant. Even proponents of immigration reform are shifting tactics, and are poised to put more pressure on President Obama to change enforcement policies rather than push stalled legislation.

THE TEA PARTY IS ALIVE AND WELL

About all those stories about the Tea Party not being relevant anymore… The only reason Cantor could be caught napping was the aggressive support Brat enjoyed among Tea Party activists who joined with national conservative voices such as Laura Ingraham and Ann Coulter to boost a candidacy nobody was paying attention to. Virginia's open primary (you didn't have to be a Republican to vote against - or for - Cantor in the GOP primary) opened the door for anyone in the district to send a message to their veteran congressman. This will embolden Tea Party activists who see the chance to defeat veteran Mississippi Sen. Thad Cochran, who is facing a runoff later this month, as their next opportunity to upend the establishment.

NOBODY IS SAFE

Cantor's loss makes his the biggest scalp in the short, aggressive history of the Tea Party movement - surely the biggest primary upset since Mike Castle went down to Christine O'Donnell in Delaware in 2010. While that cost the GOP a Senate seat even Castle didn't have the national cache of Cantor, who was widely seen as a potential successor to Boehner and was discussed as a possible vice-presidential choice in 2008. If Cantor could be caught beaten in his backyard, in a Republican primary, the list of definitely safe Republicans is alarmingly short.

THE RACE FOR SPEAKER IS ON - TO THE RIGHT

Boehner's days as House Speaker were thought to be numbered even before this stunner. Cantor's defeat ends the leadership career of the man who was most widely mentioned as his successor - a charter member of the GOP crop of "young guns" who had more credibility among conservatives than even Boehner himself. Any thought of the House Republican conference steering back toward a moderate direction in choosing a leader was zapped by Cantor's primary defeat. In elevating new leaders, House Republicans seem certain to want to push further to the right now.

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(Chip Somodevilla/Getty Images)