Republican Hopefuls Split on How to Tackle Illegal Immigration

In discussing border issues, Rick Perry said Attorney General Eric Holder should be ordered to resign over his role in the Fast and Furious gun-walking scheme.

The Texas governor went on to dispute President Barack Obama's claim that America's southern border is the safest it's ever been.

Mitt Romney proposed an identification card for people who come here legally. Employers would be required to check those cards through E-Verify or a similar system -- "or face serious sanctions."

Newt Gingrich tried to weave a middle course. Maintaining that illegal residents who have been in this country for 25 years should be granted a pass, he said he would halt federal prosecution of Arizona, South Carolina and Alabama, which have enacted tough immigration-enforcement laws of their own.

To rousing cheers, Gingrich also said he would block federal funds for communities that have declared themselves "sanctuary cities" to harbor illegals.