Mitt Romney and Newt Gingrich exchanged blows on immigration after a week in which the Gingrich campaign released a controversial ad that called Romney “anti-immigrant.” Romney halted the former speaker, challenging the language Gingrich has used to attack Romney’s stance on immigration. Gingrich said Romney’s views encouraged the searching out and deportation of grandmothers, but Romney fought back and said he was for defending the law. “I am pro-immigrant,” Romney said. “I want people to come to America … legally.” Later, CNN returned to the question, and the candidates argued again. It’s heating up. The two continue bickering, moving on to who had invested in Freddie Mac. The charge of funding the mortgage company is particularly damning in this setting, as Florida has been hit particularly hard by the housing crisis. Too bad both of them have invested in Freddie, so their attacks against each other are pretty much moot. Wolf is curious what Ron Paul thinks about this argument. He's not interested.