ORLANDO, Fla. -- On one side of Semoran Boulevard there’s Lecheron el Barrio, a Puerto Rican restaurant where a banner boasts of President Barack Obama’s summer visit. Inside, servers dish up steaming plates of pulled pork and rice and beans beneath a photo of Obama, and a largely Spanish-speaking clientele gathers in what might be the unofficial headquarters of Orlando’s Puerto Rican vote.

"Everybody I know is for Obama. It’s the culture here," said Judy Torres, 39, who was born in Puerto Rico and who dropped in recently for lunch with her husband, Luis, and 2-year-old son Cristian. Pointing to the photo of the president, she said proudly that her two daughters were at the restaurant that day.

Across the street, the Republicans have their local headquarters. Fox News airs on a big-screen television. Between calls, volunteers lunch on chicken nuggets and fries from Chick-fil-A. A bright pink sign reminds them of a deficit-based talking point: "42 cents of every dollar is borrowed." Beneath it, volunteers work the phones to urge voters to support Mitt Romney, part of a four-office brigade that combined has made more calls than any other Republican effort in the country.

“We’re not going to convert Democrats,” said Lew Oliver, chairman of the Orange County Republican Party, who oversees the phone bank. “Our main effort is making sure our Republicans vote. In a state where we are inside the margin of error in the polls, if 2 or 3 percent of our people show up more than theirs, we win. We know that works.”

Crowded with garish strip malls, used car lots and billboard advertisements for personal injury law firms, the boulevard might best represent the even divide among the voters along the Interstate 4 corridor across central Florida. In the heart of the biggest battleground state of all, both campaigns are fighting for Semoran Boulevard and every other inch of ground from Tampa to Orlando, an expanse that could well determine the outcome of the presidential election in Florida, if not the nation. Obama and Romney are neck and neck in the state.

The Interstate 4 corridor is home to not only 43 percent of the state’s electorate, but also to just about every sort of voter who exists in America. They include minority and ethnic voters in Orlando and Tampa, suburban voters in the bedroom communities surrounding the two cities, and rural voters in the strawberry fields and orange groves between the two urban centers.

"The I-4 corridor is critical," said Brett Doster, a senior adviser to Romney’s campaign in Florida. "They’re ready for a hopeful message, but one that has some gravity behind it, and one that has a record of success behind it."

Florida’s other population centers are far more predictable. South Florida votes reliably Democratic in presidential elections. With the exception of Democratic strongholds near Tallahassee and Gainesville, other parts of the state, particularly the Panhandle, are more likely to vote Republican.

Slightly younger and more transient than the rest of the state, voters along I-4 went for Obama in 2008 after voting for President George W. Bush in 2004. Obama can’t count on a repeat, though. Some of those who enthusiastically backed Obama in 2008, including some blacks, have little love for him this time around.

"Obama broke all of his promises," said Sanjai Stesty, 28, a black voter raised in Miami who now lives in Orlando. A nurse, Stesty said Obama and Romney both are too close to Wall Street. He plans to sit out this election.