In the Republican Party, immigration reform is basically a battle between the tea party, which opposes it, and the Chamber of Commerce wing, which supports it. In a nutshell, Dave Weigel explains why this means it's doomed:
The chamber wing does want immigration reform, badly, but not as intensely as it wants to defeat Democrats in 2014. So it's easy for the party to fall into a holding pattern, with new rhetoric, without actually passing a bill.
I guess anything is possible, and immigration reform has always been the one big legislative priority that I give a nonzero chance of passing Congress. But Weigel is right. The business wing of the GOP just doesn't want it badly enough to risk starting a bloody, party-rupturing fight with the social conservatives. For once, I'd say that Ted Cruz probably has the right take on this.