By Andy Sullivan

LAS VEGAS (Reuters) - A Republican debate will play out in one of this city's glittering casinos, but the real battleground for next year's U.S. presidential election lies in the foreclosure-racked neighborhoods that sprawl beyond the Las Vegas Strip's bright lights.

Few U.S. cities have been hit harder by the recession than Las Vegas, which is likely to be one of the most hotly contested prizes in an election dominated by economic concerns.

Las Vegas leads the nation in foreclosures and the unemployment rate is also among the highest.

One out of six people in the region have wondered over the past month where they will find their next meal, according to Three Square, a food bank serving the area.

"I know so many people who are desperate," said Linda Overby, a painter who has been out of work since April.

Though the economy may not pick up any time soon, Overby and other Las Vegas residents will get plenty of attention from presidential candidates over the coming months.

Nevada, which has backed the winning candidate in every election stretching back to 1976, is one of a handful of battleground states that could decide next year's election.

This time, the state's early caucus, tentatively set for January 14, will also give it an outsize influence in the Republican primary race, although some candidates are threatening to boycott the vote here due to a fight over which states should hold primaries first.

The caucus will be the first in the West, a region that features high numbers of independent and Hispanic voters and relatively few of the Christian conservatives who play a large role in other early contests.

COUNTERING THE REID MACHINE

It will also give the state Republican Party a chance to build an organization to counter Senate Democratic leader Harry Reid's machine, which helped Barack Obama win the presidency in 2008 and saw Reid through a tough re-election battle last year.

Democrats now have 100,000 more registered voters than Republicans, and Reid and other Democrats are already laying the groundwork for next year with a three-day conference focused on winning in Nevada and other Western mountain states. Obama is scheduled to visit on October 24.

Republicans say he will have a hard time repeating his 2008 victory given the state's dismal economic condition.

"Simply put, he has failed miserably to deliver on the promises of his previous campaign," said Robert Uithoven, a Nevada Republican consultant in the state who is not aligned with any candidate.

First, Republicans have to pick a candidate of their own. No opinion polls have been published since August, but insiders say Mitt Romney has the best chance of winning at this point.

MORMON FAITH COULD HELP ROMNEY

Romney's Mormon faith, which could be a liability in other states, is likely to help here. Fellow Mormons who account for 11 percent of the population helped him win the 2008 caucus and will be a factor again this time.

Romney has held several high-profile events in Las Vegas over the past few months. He unveiled his jobs plan here in September and raised $10 million in a phone-a-thon in June.

"He's been here more than anyone, he's got a solid organization, and the Mormon community will vote heavily in proportion to others," said Sig Rogich, another Nevada Republican consultant who remains unaffiliated.

Rick Perry has a powerful ally in Nevada Governor Brian Sandoval, a Hispanic, and he recently hired his first staffers in the state. But Perry's lackluster debate performances could hurt his prospects in Nevada.

Herman Cain, meanwhile, could see his sudden national popularity translate to success in the January caucus.

Ron Paul, who finished second in 2008, retains a devoted following in this libertarian-leaning state.

Candidates with strong support among Christian conservatives, like Michele Bachmann and Rick Santorum, probably will not do well in Nevada as social issues are not likely to be a factor.

In the jaws of a gut-wrenching recession, economic concerns will play an even bigger role in Nevada than elsewhere.

"Anyone who's running for the presidency is going to need to articulate some type of coherent plan," said Kenneth Fernandez, a political-science professor at the University of Nevada-Las Vegas.

(Editing by Mohammad Zargham)