GOP's No. 2 ousted by tea party upstart

• Upstart Dave Brat beat heavily favored incumbent Eric Cantor


• Brat raised less than $300,000 compared to Cantor's $5 million


• Challenger's main argument was that Cantor had turned his back on conservative principles

(CNN) -- Dave Brat, an economics professor and former seminary student, pulled off the biggest political upset of the year by ousting the No. 2 House Republican Eric Cantor in a primary challenge on Tuesday night.

"This is the happiest moment, obviously, of my life," Brat told his supporters at a post-election event in Glen Allen, outside Richmond, on Tuesday night. "The reason we won this campaign, there is just one reason, and that's because dollars do not vote -- you do."

Brat, who raised less than $300,000 to the House majority leader's campaign war chest of $5.4 million, said, "It's not about David Brat winning tonight, it's about returning the country to its principles."

Cantor failed to 'pay attention at home'

Just how surprising were the results? A close ally of Brat's told CNN shortly before the results were in that he was "shocked" and that senior campaign officials didn't believe he could pull in more than 40% of the vote. Brat ended up besting Cantor 56%-44%.

Lemon: 'Can we say holy you know what'

Cantor's team included some veteran Virginia political hands while some of Brat's top campaign staffers hadn't worked on a major campaign before.

Many political pundits were quick to credit the tea party for boosting Brat's campaign, but his campaign did not get any significant financial support from conservative groups because they were funneling money into other primary challengers they believed had a better shot at beating GOP incumbents.

'A shock on your hands'

In an interview a day before the vote, Brat made a prediction most political candidates make to try to energize their supporters, telling CNN, "On Tuesday you're going to have a shock on your hands." Brat joked that he expected to see a CNN van in his driveway to cover his victory on Wednesday.

Brat's main argument in the race was that Cantor lost touch with his conservative principles. He told CNN, "My beef with Cantor isn't not a right- or left wing thing."

Citing his expertise on economics, Brat said the GOP leader and other top congressional Republicans in Washington had set aside their "free market principles" when they backed the bailout legislation that helped bolster Wall Street banks after the fiscal crisis in 2008.

But the longshot candidate centered most of his attacks against Cantor on the issue of immigration, arguing that the majority leader's support for small measures allowing some type of legal status for children of undocumented immigrants was "amnesty." Much of the media coverage about the race focused on Brat's attacks that Cantor wasn't pushing the conservative position.

Eric Cantor: It's disappointing

Cantor worked to reassure Republicans that he would not allow any legislation to come up for a vote that provided "amnesty." He sent out mailers to Republicans in the district with the message "conservative Republican Eric Cantor is stopping the Obama Reid plan to give illegal aliens amnesty."

But Brat told CNN the issue of "amnesty" resonated more than other issues like Obamacare and jobs "because it shows Eric flip-flopping and being unprincipled."

Ad spending

In addition to the top GOP leaders' position on immigration, Brat repeatedly touted his experience as an economist, and criticized both political parties for ignoring proposals to address Medicare and Social Security.

"Neither side of the aisle will talk about the most important issues because that is going to involve pain."

While he is a political neophyte, Brat has served on state and local government boards and was a president of the Virginia Association of Economists.

Despite being the overwhelming favorite, there were signs that Cantor's campaign sensed a threat. It spent more than $1 million on television and radio ads that attempted to paint Brat as a liberal. They noted that he was appointed to one of those boards by then-Democratic Virginia Gov. Tim Kaine.

But Brat argued that Cantor's aggressive ad spending did him the favor of boosting his name identification around the district at a time when he didn't have the resources to run his own ads.

Brat, 49, grew up in the Midwest and moved to Henrico in 1996 to begin teaching economics and ethics at Randolph-Macon College, a small liberal arts institution. He has chaired the school's Economics and Business department for the past six years.

He and his wife Laura have two children.

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