On a night when the Republican presidential candidates focused their energy on undermining frontrunner Rick Perry, the Texas governor's record on immigration again surfaced as a potential weak point.

While Perry's conservative bona fides on most issues are beyond reproach, some of his immigration policies are more aligned with progressives calling for immigration reform than with the harsh enforcement approach pushed by the Republican mainstream. In 2001, Perry signed a law making undocumented students who graduated from Texas high school eligible for in-state tuition at public universities, and on Monday night his presidential rivals rebuked him for it.

Maybe that was an attempt to attract illegal -- I mean Latino -- voters, former senator Rick Santorum said.

Perry defended the position with logic similar to that invoked by congressional Democrats when they argue for the DREAM Act, a piece of legislation that would provide a path to citizenship for some immigrants who arrived in America illegally as children. Essentially, Perry said it made no sense to punish young immigrants who are fully integrated into society.

If you've been in the state of Texas for three years, if you're working toward your college degree, and if you are working and pursuing citizenship in the state of Texas, you pay in-state tuition there, said Perry. It doesn't make any difference what the sound of your last name is, that's the American way.

Rep. Michele Bachmann, R-Minn., challenged Perry on that point, continuing a line of attack launched in a radio advertisement that questioned Perry's record and warns, illegals take jobs.

The American way is not to give taxpayer subsidized benefits to people who have broken our laws or who are here in the United States illegally, said Bachmann.

Perry also appeared out of step with Republican immigration doctrine last year when he criticized Arizona's since-overturned immigration law, SB 1070, which ordered police officers to question anyone whom they suspect of being in the country illegally. Perry appeared at that time to agree with critics charging that the law was discriminatory and targeted immigrants who posed no threat to society, arguing that our focus must continue to be on the criminal elements involved with conducting criminal acts.

The Texas governor has drawn a distinction between securing the border -- on Monday, he called for more boots on the ground and faulted the federal government for lax border security -- and how to treat undocumented immigrants who are already in the U.S. That bifurcated approach reflects in part his realization Texas contains an estimated 1.6 million undocumented immigrants in addition to a sizeable Latino electorate.