From this:

Immigration is turning into an election battleground among Republicans, with several challengers running primary campaigns against leading congressional supporters of legalizing illegal aliens.

Rep. Christopher B. Cannon, Utah Republican and a prominent legalization supporter, failed to win 60 percent of the vote at a Republican nominating convention a little more than a week ago. Now, he faces a primary next month against Matt Throckmorton, a former state legislator who is running hard on the immigration issue...

"The odds are still with [Mr. Cannon], given the percentage at the convention and he's an incumbent, but here's a four-term congressman who basically gets a 43 percent vote of no-confidence from his own party's regulars," [Roy Beck of NumbersUSA] said. "For those of us who are making the argument to members of Congress that the fact that amnesties are being considered at all is a sign of great disconnect with the American population - this helps confirm that..."

Previous Cannon coverage starts here.