DORAL, Fla. - Newt Gingrich and Mitt Romney urged conservatives to back off aggressive anti-immigration policies as the Republican presidential candidates vied for Hispanic votes Friday, a day marked by heightened tensions entering the final weekend before Florida's primary.

"I'm very concerned about those who are already here illegally and how we deal with those 11 million or so," Romney said. "My heart goes out to that group of people. ... We're not going to go around and round people up in buses and ship them home."

The compassionate approach, like Gingrich's calls for politically practical reform, was aimed at improving the Republican Party's tarnished reputation among Hispanics. Both men delivered speeches Friday to the same group of Hispanic leaders gathered in Miami but avoided - at least briefly - criticizing each other in what now looks like a two-man race for the nomination.

Any calls for temperance on immigration didn't apply to personal attacks elsewhere.

The former House speaker released a new television ad in Florida using former Arkansas Gov. Mike Huckabee to question Romney's integrity. "If a man's dishonest to get a job, he'll be dishonest on the job," Huckabee says in the ad.

However, Huckabee said he didn't approve of his appearance in the ad and had been quoted out of context. Reiterating his stand against making a primary endorsement, he wrote on his PAC website: "My hope is to defeat Barack Obama and win majorities in both the House and Senate, not to attack any of the presidential candidates who might be our nominee."

Romney flashed a newfound confidence as he campaigned the day after delivering a strong debate performance. "I've had the fun of two debates where I had to stand up and battle, and battling was fun and battling was won," he told cheering supporters gathered at Cape Canaveral.

He later likened Gingrich's complaints to "Goldilocks," the fairy tale character who complained of the temperature of her porridge.

Tensions boiled over between the Gingrich and Romney representatives at a stop in Delray Beach. Gingrich spokesman R.C. Hammond confronted Utah Rep. Jason Chaffetz, who is among several high-profile Romney surrogates tailing the former House speaker.

Surrounded by reporters and cameras, Hammond goaded Chaffetz for employing a tactic that even 2008 presidential nominee John McCain has called into question. McCain is a Romney backer who on Friday said he would discourage that type of infiltration.

"What you're saying is you're disregarding the advice of one your top endorsers?" Hammond asked Chaffetz.

"Speaker Gingrich has routinely said he would follow the president from place to place. We think it's a good idea," Chaffetz responded, referring to Gingrich's threat, if he wins the GOP nomination, to follow President Barack Obama from city to city to get the last word.