Democrats like to paint themselves as the party of the immigrant. They also tend to hitch their wagon to lots of other interest groups, including women, racial minorities, sexual minorities, and endangered species (except the most endangered species on the planet, the white, straight, male.)
As an immigration attorney, I'm rather skeptical of any partisan claims to sanctity. Democrats are as political as the GOP when it comes to doing for the 'undocumented.' Yes, Republicans have a tendency to put their feet in their mouths more obviously, as when Mitt Romney made that really stupid comment about immigrants self-deporting. (The government, up until now, had a problem perfecting the deportation process, so imagine how a poor, illiterate immigrant could manage that feat.)
But the really stupid thing, worse than any malapropism from the Romney camp, is the way the Obama administration and its proxies tried to capitalize on that comment. If Obama were a wise man, he would have stayed far away from criticizing anyone about deporting 'illegals' and the manner in which it is done.
Because facts don't lie, and our current president has been more successful than his Republican predecessors in cleaning up Dodge, so to speak. According to immigratioin blogger Matthew Kolken, Obama holds the all-time record for deportations by a sitting president (or a standing one, I'm guessing.) And statistics show that his claim of targeting 'criminal aliens' is-in a word-false.