MIAMI (AP) John McCain solidified his status as the front-runner for the Republican presidential nomination with a Florida triumph, his candidacy coming full circle in little more than a year.

"It shows one thing. I'm the conservative leader who can unite the party," the Arizona senator said in a brief interview with The Associated Press.

Later, he told elated supporters: "We have a ways to go, but we are getting close."

McCain heads into next week's 20-plus contests, including mega-delegate states California and New York, with significant momentum after two straight wins and leading former Massachusetts Gov. Mitt Romney in the delegate count.

Certain to provide another boost, McCain is set to get the endorsement of Rudy Giuliani on Wednesday in California, according to GOP officials who spoke on condition of anonymity in advance of the public announcement. The former New York mayor is preparing to quit the race.

Florida provided McCain his first-ever primary victory in a state that allowed only Republicans to vote. His previous victories, in New Hampshire and South Carolina this year and in two states in his first bid in 2000, came in contests open to independents.

"Thank you, Florida Republicans, for bringing a former Florida resident across the finish line first in as I have been repeatedly reminded lately an all-Republican primary," a broad-smiling McCain said as he stood before a hotel ballroom full of supporters.

Behind him were the top two elected Republicans in the state Sen. Mel Martinez and Gov. Charlie Crist who endorsed him in the final days of the Florida campaign.

Earlier, as McCain's name flashed across giant TV screens as the winner, cheers went up and then gave way to chants of "Mac is back!" The theme from the movie "Rocky" blared before McCain took the stage.

"Our victory might not have reached landslide proportions, but it is sweet nonetheless," McCain said. "Tonight, my friends, we celebrate. Tomorrow it's back to work."

He told the AP: "It's a very significant boost, but I think we've got a tough week ahead and a lot of states to come."

Republican moderates, Hispanics and Florida's numerous older voters helped lift him to victory in Florida, and McCain led modestly among people saying the economy is the country's No. 1 issue, according to preliminary results from an exit poll conducted for the AP and the television networks.

The Florida win continues an extraordinary comeback from last summer when his campaign nearly imploded. McCain rebounded to win New Hampshire and South Carolina before rolling up Florida and its winner-take-all 57 delegates.

A loser once, McCain began his campaign just over a year ago as the presumptive Republican leader. He cast himself as the inevitable nominee in a party that historically has nominated the next in line. That distinction appeared to fall to McCain, given his 2000 loss to George W. Bush.

Conducting a front-runner's campaign to match his seeming front-running status, McCain mixed loyalists from his first campaign with veterans of Bush's two successful efforts to build an unrivaled, and enormous, national organization. He argued that he was the only Republican who could unite a wayward party reeling from a 2006 thumping that put Democrats in control of Congress.

That appearance of invincibility quickly shattered.

Internally, infighting rocked the campaign. Money was being spent faster than it came in, and finger-pointing ensued. Top aides vied for primacy, making it appear that no one person was in charge and McCain was not invested in the race. Longtime McCain aides clashed with one-time Bush aides.

Externally, Iraq and immigration took a political toll; his advocacy for a troop-increase strategy hurt him with independent voters while his backing for an eventual path to citizenship for millions of illegal immigrants infuriated the GOP's conservative base.

His standing in polls dropped and fundraising dried up.

By summer, the campaign had blown through nearly all of the $25 million it had raised, and McCain had accepted the resignations of two top aides and promoted a third to manage what was left of the campaign. Money troubles meant dozens of layoffs while loyalty to the departed aides prompted others to flee.

McCain laid low in August, working to stabilize his campaign's finances and seeking to map out a road ahead with a narrower strategy. He hoped he could still emerge as the last man standing if the GOP field remained fractured.

He looked to Florida to cement his returned status and Florida delivered.