“The Virginia electorate is so much more fluid than other states,” said Stephen Farnsworth, a political science professor at the University of Mary Washington. “It’s a very difficult environment for politicians because you have to keep re-introducing yourself to voters.”

If anything, it’s accelerating, and tilting the commonwealth’s landscape even more away from solidly Republican and more open to the Democrats.

Since 2004, nearly three quarters of a million people have moved into the state, many flocking to the sprawling suburbs outside the nation’s capital.

Democrats say the changing demographics are on their side. The census shows the state ticked up two percent in population growth in the last four years, with the increase largely among Democratic constituencies including African Americans, Asians and Hispanics. In just the last four years, Latino voter registration is up 19 percent and African American registration seven percent. Nearly 60 percent of those who have registered in the last two months are under the age of 30.

If Republicans took the state somewhat for granted in 2008 by ignoring certain regions and constituencies, they’re working overtime this fall to match Obama’s unprecedented ground game and reach their own slice of the electorate..

While Obama still has double the number of offices as Romney – more than 60 -- Republicans boast of 4.5 million voter contacts, including knocks on 1 million doors to pitch voters face to face, according to Dave Rexrode, executive director of the Republican Party of Virginia. That’s six times the phone calls and 11 times the door knocks of 2008, they said.

No longer solidly Republican red, and definitely not Democratic blue, this piece of the old South is instead a deep purple at the state level with the pendulum swinging back and forth between Democratic and Republican wins as independents determine victories based on candidates, not parties. A U.S. Senate campaign between two former governors – Republican George Allen and Democrat Tim Kaine – is neck and neck.

“People want mainstream government,” said Sen. Mark Warner, D-Va., a cell phone executive turned popular governor who used his moderate pro-business record to persuade independents, even in rural regions, to vote for him.

Virginians, he said, opt for a change when either party moves too far from the middle.

Since Obama’s win four years ago, the state turned away from Democrats and largely back to the Republicans, who now control the Governor’s office and the legislature. Republicans hold a commanding majority of Virginia’s congressional delegation, though both U.S. Senate seats now are held by Democrats.

Democrats have made the most inroads in the Northern Virginia suburbs outside Washington, where one in three voters now lives. Republicans have electoral strength in the southern and western regions.

But the key battleground areas full of independent voters are the exurbs of Washington and Richmond as well as Hampton Roads, the sprawling region in southeastern Virginia and home to a large number of veterans as well as college students and African-Americans.

Republican Gov. Bob McDonnell was the first Virginia Republican in recent years to forgo his conservative roots in lieu of a moderate, pragmatic approach centered on kitchen-table issues, such as jobs and schools, and an emphasis on the diverse new populations in northern Virginia, including Hispanics and Asians. It’s a strategy Romney is trying to emulate.

McDonnell said Virginians are focused on economic issues, such as federal spending and impending defense cuts – the Pentagon is in Northern Virginia, the Navy dominates the Hampton Roads. Social issues don’t matter as much, he said.

“Governor Romney is pro-life. Barack Obama is radically pro-choice,” he said. “But that’s not what people are voting on.”

David Lightman contributed to this article.

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