On Tuesday, Democrats will hold primaries in two big states, Texas and Ohio. The latter has long been a bellwether of American politics, and no one has won the presidency without winning Ohio since John F. Kennedy, nearly 50 years ago.
If Democrats had carried Ohio in the last two elections, they would have won the White House, and Ohio voters will play a large part in determining who the Democratic nominee will be in 2008 and, perhaps, whether Hillary Clinton can keep her candidacy alive.
Correspondent Steve Kroft talked with Sen. Clinton and Sen. Barack Obama as 60 Minutes followed their campaigns in Ohio this past week.
"I know your husband has said and other people have said you've got to win these two states to stay in the race. Do you agree with that?" Kroft asked Sen. Clinton.
"Well, I intend to. I intend to do everything I can to win them. And we're doing well," Sen. Clinton replied.
"Do you like your chances of winning one of the two big primaries that are next Tuesday?" Kroft asked Sen. Obama.
"I think we've got a good shot," the senator from Illinois replied.
There's no better place to find out than Ohio: it's the heartland of America, one of the big states in the middle of the country that has always grown the food and made the things that America needs - from auto parts to soap and shampoo to hamburgers.
It stretches from the Great Lakes to the Ohio River, from Appalachia to the plains of the Middle West. If Ohio were a country it would have the 25th largest economy in the world, just behind the Netherlands. But today it reflects the problems and the challenges facing the United States and its middle class in a world that is rapidly changing.
From Youngstown and Cleveland to Akron and Dayton, Obama and Clinton have crisscrossed a state that could put one of them in the White House. In the eight years that George Bush has been president, Ohio has lost more than 200,000 manufacturing jobs and the state's median income has fallen by nearly ten percent.
It's being felt in the small cities that dot the Ohio landscape and could very well decide the primary. It's places like Chillicothe, a town of 22,000 people an hour south of Columbus.
Chillicothe is a political microcosm of the state of Ohio: in the past two presidential elections, the voting patterns here have been virtually identical to the statewide results. George Bush and John Kerry campaigned for president here; so did Bill Clinton, Richard Nixon, Harry Truman, and Teddy Roosevelt.
One reason may be that the politics here are unpredictable. Chillicothe has more independents than Republicans and Democrats combined. And all of them are eligible to vote on Tuesday.
Steve Madru, the Democratic chairman of Ross County, thinks the town is not only a mirror of Ohio, but the whole country.
Every evening he turns his real estate office in Chillicothe into the campaign headquarters for Senator Clinton.
"My sense of it is that a lot of the party establishment, a lot of the party machinery, is behind Hillary?" Kroft asked.
"Yes, pretty much," Madru agreed. "I think it's, you know, Ted Strickland, our governor, is behind Hillary. And he's done such a great job in Ohio. And he's friends with the Clintons. And a lot of us kind of follow along with the governor."
A month ago that organizational support had given Sen. Clinton a 20-point lead in Ohio polls, but much of it has evaporated with 11 straight defeats and the rise of a dedicated corps of Obama supporters who have been canvassing neighborhoods and taking their own informal street corner surveys by gauging how many people honk at their campaign signs.
"You assume that people honking are people that like you?" Kroft asked campaigner Chris Cooper.
"Well, when they give you a thumbs up, they like you. When they give you the finger it's a thumbs down. So, I'm pretty sure those are international symbols," Cooper replied.