Sen. John McCain (R-Ariz.) warned Mitt Romney, in an interview published Monday at The Daily Beast, that the presumptive GOP nominee needs to soften his rhetoric on immigration if he wants to win Latino voters.

In the interview, McCain said that he and Sen. Lindsey Graham (R-S.C.) called Romney in January to urge him to tone down his rhetoric, and he did. The candidate hasn't used the phrase "self-deportation" since, according to the Daily Beast.

Romney is up against low numbers for Latino support, with a recent Latino Decisions poll finding that he has only 22 percent support to President Barack Obama's 70 percent.

Conventional wisdom among strategists is that Republicans need about 40 percent of the Hispanic vote to win a presidential election. Former President George W. Bush won 44 percent of Latino voters in 2004, according to some estimates. McCain received about 31 percent of the Latino vote when he lost to Obama.

McCain worries that Romney will do even worse, The Daily Beast reported.

"He gets 24 percent of the Hispanic vote," McCain told the publication. "They need to do more outreach."

Romney said in a GOP debate in January that "self-deportation" -- essentially making life difficult for undocumented immigrants until they decide to leave -- would be the best policy for lowering the number of people in the country without authorization.

"The answer is self-deportation, which is, people decide they can do better by going home because they can't find work here because they don't have legal documentation to allow them to work here," Romney said.

After the Obama administration announced in June it would halt deportation for some undocumented young people, McCain bashed the decision as "a politically motivated power grab that does nothing to further the debate but instead adds additional confusion and uncertainty to our broken immigration system."

But he notably declined to call the move "amnesty," the term thrown at many efforts to stop deportation for undocumented immigrants.

McCain was a centrist himself on immigration until his failed bid for president in 2008 and his 2010 reelection campaign, when he went from a supporter of comprehensive immigration reform and the Dream Act to a "complete the danged fence" would-be hardliner. Since his reelection, he's returned somewhat to his roots -- although he voted against the Dream Act when it went for a Senate vote in 2010 -- and said he hopes to see some sort of congressional action to address young undocumented immigrants.

Romney said he wants the same, but has failed to give any details on how he would deal with the issue, including a refusal to say whether he would end the Obama policy that gives reprieve to some undocumented young people.

CORRECTION: This article was corrected to reflect that McCain's ad on border fences was in 2010, not 2008.

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  • 10. Nevada - 181,850 Potential Latino Voters

  • 9. Virginia - 200,900 Potential Latino Voters

  • 8. New Mexico - 202,650 Potential Latino Voters

  • 7. Georgia - 208,200 Potential Latino Voters

  • 6. Colorado - 242,750 Potential Latino Voters

  • 5. Arizona - 575,300 Potential Latino Voters

  • 4. Florida - 1,348,400 Potential Latino Voters

  • 3. New York - 1,487,600 Potential Latino Voters

  • 2. Texas - 3,034,600 Potential Latino Voters

  • 1. California - 4,496,500 Potential Latino Voters