This goes back to what I was saying in another thread:
http://forums.sherdog.com/forums/showthread.php?p=110139505. The U.S. was founded as an experiment in liberalism, and politically, we're still kind of waking up after a long period of a strong liberal consensus. As a result, few people in politics openly argue against liberal values--freedom, equal rights, democracy, governance guided by reason, etc. The arguments are framed as arguments about factual or technical matters. "Do higher deficits drive growth when interest rates are as low as they can go?" rather than, "should gov't do anything about recessions, particularly when the rich end up paying a bigger portion of the relief effort?" Or note how everyone agrees that racism is irrational and destructive--even people who hold racist beliefs and feelings (they just deny that that's an accurate description!).
So Sherdog liberals and leftists tend to think, "Well, that guy is just wrong about a question with an objective answer. Let me correct him (not necessarily in a respectful way)." But rightists have a better grasp on what's really going on on their own end (and a worse grasp of what's going on on the other end). They realize that the arguments are not really what they're about, but they think that's symmetrical. So rightists think that when someone says, "climate change is real," they're really saying, "I want the gov't to take greater control over our lives." And when someone says, "we can reduce unemployment with temporarily higher deficits," rightists interpret it the same: "I want the gov't to take greater control over our lives." When someone notes the obvious objective success of healthcare reform, it's the same. And so on. If one guy thinks, "oh this dude is getting something wrong," and the other thinks, "this guy is trying to enslave me," there's going to be a big passion gap.
I think it makes a lot more sense that immigration is the key issue in the GOP primary than tax cuts for the rich. The GOP base goes along with tax cuts for the rich because it's an identity issue, but they HATE immigration and immigrants, and a lot of them have no trust that the party leadership is with them on that issue. Further, a lot of people on the left are also passionately anti-immigration and that view doesn't have much representation in Democratic Party so a Republican strong on that issue might get some crossover votes. The GOP would be a lot more successful making immigration a big issue than they have making upward redistribution a big issue.