WASHINGTON -- Eleven states are likely to decide whether President Barack Obama or Republican Mitt Romney will be elected president Tuesday.

The winner needs to cobble together 270 electoral votes. Estimates by the website RealClearPolitics.com say that Obama can count on 201 and Romney 191 in the three-fourths of the nation where they look solid.

That leaves the battlegrounds. Spread across America, the swing states often share several characteristics: recent population increases, meaning lots of new voters; growing numbers of Latino voters; diverse populations that mirror the nation’s demographic makeup; and economies that are recovering slowly.

The biggest prize is Florida, whose 29 electoral votes would give the winner more than 10 percent of what he needs for election. So far the battle for the Sunshine State is a virtual tie.

The states to watch first on election night are Virginia and North Carolina. Both went Democratic in 2008 for the first time in decades, but they show signs of inching back to the Republican side. Also worth eyeing is New Hampshire. In a close race, its four electoral votes could matter, and polls suggest either candidate could win.

Move west, and there’s the day’s most reliable bellwether, Ohio. No Republican has ever won the presidency without it, and no one has won the presidency, period, without the Buckeye State since 1964. Obama’s up by a healthy average of 4.6 percentage points in recent statewide polls.

Should the race remain tight Tuesday night, attention will turn further west, first to Iowa and Wisconsin, and then to the night’s final battlegrounds, Colorado and Nevada. Each has seen increases in their Hispanic populations, and surveys show Latinos are overwhelmingly for Obama. But will they turn out?

The fight for the sliver of undecided voters in the battleground states is unusually fierce. Estimates are that the two campaigns and their parties will each raise more than $1 billion. Obama’s forces have opened more than 100 campaign offices in both Florida and Ohio. Romney’s camp boasts that its workers have knocked on more than 2 million Ohio doors.

Then there’s the "October surprise," Hurricane Sandy. Obama left the campaign trail for three days so he could monitor and manage the federal response to the storm. Romney suspended campaigning for a day and a half and helped Ohio supporters prepare relief supplies.

Will it help that Obama was able to vividly remind voters that he’s in charge? Or will Romney, who resumed campaigning Wednesday, score with his relentless assault on Obama’s economic record at a time when people still lack confidence?

All the polls agree: It’s too close to call.

FLORIDA (29 electoral votes)

The latest surveys show a tight race. Lines for early voting, which ends Saturday, remain long. And there could be as many as 2 million absentee ballots to count.

As of Thursday morning, Democrats held a 59,000-ballot advantage over Republicans in total pre-Election Day votes cast. But Republicans pointed out that, compared to 2008, Democrats aren’t in the position to rack up a major early-vote lead.

Part of the reason is that the Republican-led Legislature last year cut early voting days in the state to eight, down from 14 in 2008. In all, Democrats edged Republicans by 133,000 early-vote ballots over the last five days, but Republicans extended their absentee-vote lead to more than 74,000.