The Huckabee data is quite interesting. He gained an average of 2.79% or 3.6% via his stance on immigration compared to McCain. The lower value is compared to how he did with all voters. The higher number is how Huckabee did compared to non-immigration voters. Either way, the gain to Huckabee from immigration is quite similar to his winning margins in AL, GA, and TN. Not bad for a candidate who didn't really stress immigration.
The "How to Handle Illegal Immigrants" question yields some interesting results. "Deport Them" outpolls "Path to Citizenship" in all cases. In many states (5), "Deport Them" scores above 50%. However, the real question is how to interpret "Temporary Worker". The folks pushing for TW status usually (but not always) mean "temporary" as in the next 100 years. However, primary voters probably assume that "temporary" means "temporary". Combining TW and DT shows that over 70% of primary voters oppose Amnesty.
Notably, 21% of primary voters selected illegal immigration as their main issue. Michigan ranks lowest at 13% and Arizona ranks highest at 31%. California is also quite high at 29%.