In Nebraska, they have a name for this year's gubernatorial contest: They're calling it "Three Davids and a Goliath." One of the candidates is the incumbent, but surprising as it may seem, he's not Goliath. He's one of the Davids.

Goliath is Tom Osborne, the revered University of Nebraska football coach who's now serving his third term in Congress. Osborne routinely gets raucous welcomes wherever he campaigns; he received a standing ovation from a crowd of World War II veterans at a recent Nebraska State Fair. "You don't need to do that," Osborne told them. "I'm not the football coach anymore. I'm just a politician."

When Osborne announced for governor last year, polls showed him with a 30-point lead over Governor Dave Heineman, who acceded to the top spot in January 2005, when predecessor Mike Johanns joined the Bush cabinet. Two other candidates share the governor's first name; that's how the Biblical reference got started.

But those who take the reference seriously might want to keep one fact in mind: Goliath lost. And Osborne has been running into some problems as he prepares for what he hoped would be a routine primary victory.

This is mainly because Heineman has exploited incumbency to full effect. He pushed through a big economic development and tax incentive plan last year, and a rising economy has allowed him to propose $420 million worth of tax cuts perfectly timed for the upcoming GOP primary in May. He's taken a politically popular stance against school consolidation in the Omaha area, and closed a huge agriculture trade deal with Cuba, the biggest any state has cut with that country. Nebraska farmers may not care for Castro, but they love higher wheat prices.

While Heineman has been making constant public appearances, Osborne has been stuck in Washington much of the time. His self-imposed campaign contribution limits, seemingly a good idea when the primary looked like a cinch, may be hurting him now that Heineman is mounting a serious threat. And the congressman's most prominent issue, a call for performance reviews to promote greater efficiency in government, hasn't exactly set the stump on fire, especially in comparison with Heineman's tax cuts and job promotion.

Perhaps most important, Heineman has left Osborne with little room to argue that he'd change the present course much--or even that the course needs changing. "Politically, it's very difficult for Osborne to carve out policy distinctions between them," says John Hibbing, a political scientist at the ex-coach's old university.

At this point, the race is close. Osborne still enjoys the power of celebrity, and his congressional district is home to about 45 percent of Republican primary voters. But in order to dodge Heineman's slingshot, he's going to have to convince a lot more Nebraskans that he's not just a politician but in fact the more capable one.