COLUMBUS, Ohio — If Rick Santorum is ever going to be president, he's probably going to have to show it in Ohio.
He's falling farther behind front-runner Mitt Romney by the week. He needs a win in a delegate-rich battleground state to show the rest of the country he can overcome Romney's moneyed campaign machine, and to start gaining ground in the delegates needed to win the Republican nomination.
Win Ohio, and Santorum could grab his best shot at overtaking Romney.
Lose it, and Santorum will fall farther behind in delegates with a shrinking field of opportunity to make up ground. Worse, he'd have a devil of a time explaining how he lost a state where conservatives, evangelical Christians and blue-collar workers offered him a fertile hunting ground for support similar to his home state next door.
Arriving Friday for a weekend full of Ohio, Santorum explained the outsized importance of the state heading toward caucuses and primaries in 10 states on Tuesday. "You seem to always be the center of the political universe in America," Santorum said at a rally in Willoughby, east of Cleveland.
Polls show the race neck and neck between Santorum, the former senator from Pennsylvania, and Romney, the former governor of Massachusetts. Former House Speaker Newt Gingrich and Rep. Ron Paul of Texas lag far behind.
For Santorum, the best shot might come from social conservatives in small towns and suburbs who applaud his outspoken stands on issues such as abortion, gay marriage and government-mandated free contraception.
"He takes a sturdy stand for the family," said January Batten, a stay-at-home mom who home-schools her five children in Kettering, outside Dayton.
"Being pro-life is the number one issue," said Gwen Sobieski, a stay-at-home mom from Kettering. "I listen to a lot of Christian and Catholic radio. I've heard him interviewed. He's very strong on it and always has been."
Born-again Christians or evangelicals make up about 40 percent of the likely voters in Ohio, according to a poll by Quinnipiac University. Santorum gets 40 percent of them, almost as much as Romney's 23 percent and Gingrich's 21 percent combined.
Some activists fear, though, that social conservatives might be turned way by the fear that Santorum would drive away independents and lose the general election.
"Don't listen to the conservative media establishment," activist Maggie Gallagher told about 50 people at pro-Santorum social conservative rally in a strip mall parking lot in Kettering.
"They're giving you a false choice. They're telling you that somehow you have to choose between a candidate who can get elected and a candidate who cares deeply about all of your values. ... Frankly, Republicans always do better when they have a strong conservative who can rally the base."
Santorum needs help from activists such as Gallagher, as he lacks the money or machinery to advertise heavily or get out the vote.
Another challenge: Lacking staff when it was critical to look ahead, he failed to slate delegates in all of Ohio's congressional districts. He could lose the chance to win as many as 18 of the state's 66 delegates.
At the same time, Santorum faces a test in places such as the upscale suburbs of Columbus where voters tend to care about the economy, not social issues. They're breaking for Romney.
"Romney would be wonderful for the economy," said MaryLee Duvall, a retired financial planner from Upper Arlington, a Columbus suburb that's home to administrators and faculty from Ohio State University as well as attorneys and other professionals from the city.
"We lean toward economic issues. We need to get back to the economy. There is an arm of the Republican Party that's run away with social issues. They've gone berserk. It's a matter of priorities. If we were rocking and rolling on the economy, that would be one thing. But we're not."
The economy is improving in Ohio. Unemployment dropped to 7.7 percent in January, lower than the national average. Even manufacturing jobs are starting to grow. But it still tops the list of concerns.
"Romney knows how to create jobs, private sector jobs," said Judy Brachman, a retired government administrator from Columbus.
"The important issues are economic. I don't see Santorum focusing on those issues. They're important to him personally. Fine. But for the country and for Ohio, the economy is more important."
Ann Romney, the candidate's wife, agreed during a stop at campaign headquarters in Columbus Thursday. "The message that's resonating," she said, "is an economic message."
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