Republican George Allen is once again looking to the White House and a Democratic president to help boost his chances of winning Virginia's hotly contest U.S. Senate race.

Allen is aiming to overtake his Democratic rival, Tim Kaine, by relaunching his effort to link Kaine to President Obama, who won Virginia four years ago but has seen his popularity in the commonwealth flag since then.

For weeks, as Obama's poll ratings in battleground Virginia were rising, Allen virtually stopped mentioning the president. But as Republican Mitt Romney in recent weeks erased Obama's lead in Virginia, Allen is again bashing Kaine with claims that he supports Obama's agenda.

"Obviously, Romney feels better about his chances of taking Virginia than they did three weeks ago, and Allen must as well. Allen had almost stopped talking about Obama for a while," said Bob Holsworth, a longtime observer of Virginia politics. "Allen wants to limit crossover votes for Romney to Kaine."

Allen now portrays Kaine as "Obama's senator" and claims that, as governor, Kaine spent more time working on national politics and to elect Obama than he did on state business. After Obama was elected, the president tapped Kaine to chair the Democratic National Committee.

"Instead of focusing on jobs for Virginians, Tim Kaine championed President Obama's agenda for the failed stimulus, the cap-and-trade national energy tax and Obamacare, with an increase of over $5 trillion in our national debt," said Allen campaign manager Mike Thomas.

Kaine made light of Allen's strategic shift.

"I like being called 'senator' before the election," he told Fairfax voters Wednesday.

In addition to linking Kaine to Obama, Allen is embracing Romney. After months of touting his own agenda, "Blueprint for America's Comeback," instead of Romney's, Allen this week lauded Romney for "showing leadership" on a plan to avoid looming defense cuts.

Kaine hasn't distanced himself from Obama, but he has drawn distinctions with the president on key issues, like Kaine's support for oil exploration off Virginia's coast. That strategy has allowed Kaine to win over some Romney voters.