For all the fanfare of a marquee race between two evenly matched political heavyweights, the battle for Virginia's open U.S. Senate seat has lacked fireworks.

Republican George Allen and Democrat Tim Kaine, both former governors and seasoned campaigners, happily avoided controversy and personal attacks and steered a wonkish war over policy differences to deadlock for more than a year.

But Kaine has opened a narrow lead over Allen in the campaign's final days -- 50 percent to 46 percent in the latest Quinnipiac University poll -- despite having produced the campaign's only real gaffe and a barrage of attack ads funded by outside groups.

While turnout will ultimately decide the winner, Allen's inability to pull ahead of Kaine stems from the head winds his campaign faced since the start.

Unlike Kaine, who ran unopposed in the primary, Allen faced challengers who questioned his conservative credentials as a Bush-era Republican. And after outspending his opponents in the 2000 and 2006 races, Allen has regularly trailed Kaine in fundraising.

And while Allen was a popular governor, some voters remember him more for his 2006 "macaca moment," when he called an operative from his opponent's campaign by a perceived racial slur. He's repeatedly apologized for the incident, but it remains an issue.

"Allen has to reintroduce himself to voters who haven't seen him in a while or may be too young to remember his days as governor [from 1994 to 1998]," said Stephen Farnsworth, a political scientist at the University of Mary Washington. "And the 2006 election, for those who remember it, was not George Allen's finest hour."

In waging his political comeback, Allen built his campaign around the premise that voters dissatisfied with President Obama's record on jobs and health care would be equally turned off by Kaine, an Obama ally picked by him to chair the Democratic National Committee.

But voters are equally dissatisfied with a gridlocked Congress, and Kaine used Allen's attacks to paint the Republican as representative of all that's wrong with a divided Washington already.

"They thought that running against 'Tim Obama' would be enough," said Paul Goldman, a longtime Democratic strategist. "In the 1990s, it was easy to slam the Democrats, and George was very good that way. But I don't think that's where Virginians are at right now. He needed to project a new Allen in this race. You can't recreate the old image."

Virginia Republicans believe enthusiasm remains on their side, and polls show independents backing Allen over Kaine. They also see a boost for Allen as the party's presidential, Mitt Romney, improves his standing in the Old Dominion.

But even Republicans are starting to believe that Romney must win handily to bring Allen along with him.

"Neither Allen nor Kaine has sought to become controversial in the race, and that means the sharp differentiations are muted and they're riding with their presidential candidates," said former Republican Gov. Jim Gilmore. "I'm of the opinion that Romney is going to win Virginia. But we don't know yet how the Senate race will come out. If Romney gets a little bit of a margin, I think he pulls Allen in."