Florida Sen. Marco Rubio argued Thursday that anti-immigration policies were "not a conservative principle."
At a breakfast organized by the Christian Science Monitor, Rubio told reporters he did not think Mitt Romney was vague on immigration, and in fact had already "laid out... the broad perimeters of a precise process on immigration."
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Romney will address one of the biggest Latino conferences in the country in Orlando Thursday, and Rubio said he was looking forward to hearing what the candidate would say about the issue.
Rubio's words, however, stand in stark contrast with reports that say Romney may avoid immigration altogether in his speech.
The candidate will avoid it, the Guardian reports, because Romney has "no plan of his own" for how to deal with illegal immigration.
Romney has been walking a tightrope on the issue since President Obama announced last Friday that the U.S. would stop deporting young illegal immigrants who had gone to college or served in the military.
In the 2012 campaign, Romney has often "run to the right" on immigration, according to the Washington Post, at times using the word "illegals" to refer to illegal immigrants.
When Rubio was pressed by reporters about whether he fully approved of Romney's current stance on immigration — the issue about which the Flordia senator is most passionate — he briefly stuttered and then said: "I think he'll continue to develop as the campaign goes on."
Rubio also conceded that some "people on the right" had been "guilty of saying outrageous things" about immigration in the past.
Rubio, a rising star in the GOP, is one of several names widely cited as a possible Romney VP.