In the days when he supported comprehensive immigration reform, Sen. Marco Rubio (R-FL), the son of Cuban immigrants, seemed like the one person who might be able to repair the GOP’s damage to its brand with Hispanic voters.

But compassion for immigrants collided with reality when Rubio, a contender for the Republican presidential nomination in 2016, ran into a GOP base that remains adamantly opposed to immigration in general and easing the penalties on illegal immigration in particular.

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Rubio has already disavowed the immigration compromise that he supported in the Senate last year. And this week he drifted even further to the right, giving interviews to right-wing media outlets in which he raised the specter of a government shutdown in the fall if President Obama takes unilateral action on the immigration front. He also suggested there will likely be no new legislation this year to deal with the immigration issue, including with the thousands of unaccompanied minors crossing the border illegally.

Speaking to Breitbart.com in an interview published earlier this week, Rubio expressed concern that President Obama would unilaterally grant amnesty to an untold number of illegal immigrants currently in the country – and said this action could lead to another government shutdown battle.

“There will have to be some sort of a budget vote or a Continuing Resolution vote, so I assume there will be some sort of a vote on this,” Rubio said. “I’m interested to see what kinds of ideas my colleagues have about using funding mechanisms to address this issue.”

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In an interview with the Washington Examiner’s Byron York, Rubio also said the president isn’t likely to see any legislation dealing with immigration reform come out of Congress any time soon.

“The fundamental impediment to making progress on immigration is that people in this country – a large number of Americans and their elected representatives in Congress – do not believe that, no matter what you put in the law, they don’t believe the federal government will enforce it,” he said.

This leaves the Obama administration in a difficult position with regard to what both parties have described as a “crisis” on the southern border. If the president acts unilaterally, he risks another government shutdown fight. If he waits for congressional legislation – it is likely he’ll never see any.

Clearly, the Marco Rubio roaming around Washington these days is very different from the senator who, just last year, worked with conservatives’ favorite senatorial boogeyman, Chuck Schumer (D-NY), on comprehensive immigration reform.

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The change in Rubio’s attitude change was on full display during a Monday speech in South Carolina, when he was interrupted by protesters who called for relaxed immigration laws. As the Washington Post’s Manuel Roig-Franzia pointed out, when confronted by a similar group two years ago, Rubio was magnanimous, asking the security guards to allow the young people to stay and listen to his speech.

On Monday, though, he responded initially with sarcasm – then followed up with a brief lecture, telling the protesters, “You’re doing harm to your own cause. You don’t have the right to illegally immigrate to the United States.”

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