(Fixes slug to USA-POLITICS/ROMNEY, edits)
By Jason Szep
JACKSONVILLE, Florida, Jan 21 (Reuters) - Voters had a glimpse into Mitt Romney's strategy for winning the Republican nomination and the White House when he leapt onto the back of a flatbed truck shortly before his victory in Nevada.
After handing out doughnuts, Romney told supporters in a Las Vegas suburb his eyes were on California -- a delegate-rich state with big sway on Feb. 5 "Super Tuesday," when more than 20 states will hold contests for the nominees in the November presidential election.
To drive home the point on Friday, Romney was with a Californian niece, Kristen Hubbs. "It's going to be a long, fun campaign," said the former Massachusetts governor. "I had no idea how long it was going to be."
Backed by his $250 million fortune, Romney is in a battle of attrition. Supporters expect the next big nominating contest in Florida on Jan. 29 to winnow the crowded Republican field to just two: the surging John McCain and Romney.
Wild cards are former New York Mayor Rudy Giuliani, who has staked his campaign on Florida, and Mike Huckabee, the former Arkansas governor and Baptist preacher especially popular with evangelical Christians.
Polls have the four close in Florida. McCain's Jan. 19 victory in South Carolina gave momentum to the campaign of the 71-year-old Vietnam War hero and four-term senator from Arizona, on top of his win in New Hampshire on Jan. 8.
Romney and McCain both plan weeklong dashes across Florida, where a major concern is an economy struggling with a housing crisis and rising unemployment.
"It's a huge challenge, but if Romney can pull off Florida and do really well there then he's really in the driver's seat with his organization and money," said Thomas Whalen, a professor of politics at Boston University.
Supporters contend that if he does well enough in Florida to face McCain in a two-way race on Feb. 5, Romney can unite the social, economic and security wings of the Republican Party, whose establishment has clashed with the maverick McCain over issues like campaign finance reform.
They largely discount the role of religion -- Romney would be the first Mormon president -- saying that while some conservative Christians consider Mormonism a cult, Romney has support among many evangelicals.
"There's a lot of smoke and mirrors on that issue. I don't see his religion as a factor. He has good family values, and he's a credible candidate," said David Runyon, an evangelical Christian voter in Jacksonville.
Romney's supporters see some risk "Super Tuesday" will not produce a clear nominee after the most wide open race for the Republican nomination in 50 years.
But they contend that the former venture capitalist's deep pockets could be decisive. He would have the resources to campaign hard in states where the flagging economy could draw voters to his CEO image.
"The only way you're going to have somebody who understands how to rebuild an economy is to have somebody who's been in the economy, who knows what it's like to see jobs come and go," Romney said on Fox News on Sunday.
After winning in his native Michigan, thinly contested Wyoming and Nevada while finishing second in Iowa and New Hampshire, Romney has the most delegates of the Republicans. He has 72, versus McCain's 38, Huckabee's 29 and Giuliani's two.
"We're not concentrating on just one region or a few states," he told reporters in Jacksonville.
That strategy could be derailed in Florida, where Sen. Mel Martinez, a Florida Republican popular among Hispanics, and Gov. Charlie Crist, for example, have been at odds with Romney over immigration.
Exit polls from South Carolina, where Romney finished fourth despite outspending rivals on advertisements, showed Romney has difficulty shaking a perception that he shifted positions for convenience on emotive issues like abortion.
Among voters who told exit pollsters the main reason they voted for a candidate was because he "says what he believes," Romney finished last. (Editing by Patricia Zengerle)