The defeat of House Majority Leader Eric Cantor is likely to significantly chill efforts to pass an immigration reform bill this year.

Cantor, R-Va., was defeated by Dave Brat, an economics professor who relentlessly attacked Cantor over his ambiguous stance on comprehensive immigration reform and his backing of a plan to legalize people who came here illegally as children.

“It's the most symbolic issue that captures the differences between me and Eric Cantor in this race,” Brat told Fox News after winning the race.

Cantor, along with House Speaker John Boehner, R-Ohio, and other GOP leaders, said he wanted to to pass immigration reform, perhaps this year, by taking it up in pieces.

But they have yet to schedule a vote on a single immigration reform bill and now are far less likely to do so in the wake of Cantor’s shocking loss.

“It seems like this kills any more talk about an amnesty deal this year,” said Roy Beck, president of NumbersUSA, a group that lobbies to reduce immigration. “And it also seems to suggest that when Republicans get together in December to elect their leadership, I think the leadership is going to have to pledge something and not be like Cantor on immigration.”

Brat contrasted himself with Cantor by promising voters he would oppose any House measure that could lead to legalization of amnesty for illegal immigrants. Brat also clearly outlined his opposition to most other aspects of reform that would increase the nation’s immigrant population.

Cantor, however, took a less defined stance on immigration reform. But he authored a plan that resembled the Democratic “Dream Act” to allow young illegal immigrants to become citizens eventually.

"One of the great founding principles of our country was that children would not be punished for the mistakes of their parents,” Cantor said in a 2013 speech. “It is time to provide an opportunity for legal residence and citizenship for those who were brought to this country as children and who know no other home."

Brat told voters he opposes Dream Act legislation.

Cantor’s ouster was aided by conservative talk radio hosts, including Laura Ingraham and Mark Levin, who frequently promoted Brat on their programs. Ingraham held a campaign rally for Brat. The two hosts are staunch opponents of comprehensive immigration reform that includes legalization or a pathway to citizenship, which they call amnesty. They say it will lower wages by increasing the workforce and strain the social welfare system.

Ingraham said the immigration reform debate helped boost Brat and is a lesson to the GOP leadership that has pushed immigration reform over the objections of its most conservative faction.

Opponents say the GOP leadership has caved to big businesses, who want to expand the workforce through comprehensive immigration reform in order to lower wages.

Voters, Ingraham suggested on Fox News on Tuesday night, “are really tired of business as usual in Washington and the establishment mindset that shoving down this amnesty deal is the only way for the Republican party to survive.”

She added, “This is a massive wakeup call to the Republican party. If they actually choose to wake up.”

Still, other pro-immigration reform incumbents survived their Tuesday primaries, including Sen. Lindsey Graham, R-S.C., who is an author of the Senate comprehensive immigration reform bill, which includes a pathway to citizenship.

But in Cantor’s race, immigration reform became the dominant issue, highlighted even further this week with the influx of thousands of children crossing into the United States illegally and unaccompanied by their parents.

Cantor, who vastly outspent Brat, began to realize his vulnerability on immigration reform and started playing defense on the issue. He sent flyers to the homes in the 7th District promising to stop the “plan to give illegal aliens amnesty” proposed by Democrats.

It’s a label Cantor never used on Capitol Hill, particularly when talking about those here illegally who would qualify for his Dream Act program.

“For Eric Cantor to say he was against amnesty, while promoting it for certain groups,” Rep. Tim Huelskamp, R-Kan., told the Washington Examiner, “I guess that wasn't very believable.”