But recent polls, the state's demographics and its history in presidential elections make clear that if Virginia really is a battleground, it's Obama who has the uphill fight.
Even Obama's most ardent and influential Virginia backer acknowledges that the Illinois senator faces a difficult but not impossible task to become the first Democrat to carry the state since 1964.
"He is an underdog because this 44-year drought did not happen by accident," said Gov. Timothy M. Kaine, one of Obama's earliest backers and a finalist to be his running mate.
Republicans excited their voters in Virginia with McCain's choice of Alaska Gov.as his running mate, Kaine said. Even so, he added, Obama's supporters still have plenty of energy.
Frank Atkinson, a longtime GOP adviser and author of two books on the party's ascendancy in Virginia, said McCain probably will prevail because of his edge among voters tied to the state's large military and defense industry interests.
"If Virginia is close, it probably means this state won't be a battleground because Obama has probably won the election handily," Atkinson said.
Virginia is not the same Republican redoubt it was eight years ago when George Bush beat Democrat Al Gore in the state by 8 percentage points, and Republican George Allen swept Democratic incumbent Sen. Chuck Robb from office. That election briefly gave the GOP control of every statewide elected office and both legislative chambers.
Since then, Kaine and his Democratic predecessor, Mark R. Warner, have dominated two gubernatorial elections and Allen was denied re-election by Republican-turned-Democrat Jim Webb.
"You've got more Democratic voters there, probably more independent-minded voters who are behaving more Democratically," said David Plouffe, Obama's campaign manager.
Mo Elleithee, a Democratic strategist and veteran of three Virginia campaigns, said Obama is to be credited for putting up a fight in Virginia.
"Eight years ago, the thought of a Democrat even setting foot in Virginia in a presidential race was a totally foreign concept," Elleithee said.
Obama trailed McCain by 6 percentage points in a CNN/Time/Opinion Research Corp. poll of 920 registered Virginia voters last week. Other polls have shown a McCain advantage of from 3 to 5 points.
Obama is contesting areas normally not amenable to Democrats in presidential elections, including rural and overwhelmingly white southwestern Virginia, a region reeling from disappearing manufacturing jobs.
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"Compare that to 2000, when Al Gore didn't even cross the Potomac," said Elleithee.
Warner, Kaine and Webb won with variations of the same script that Obama is now using: undercut Republican strength in rural areas, energize Democratic-voting urban areas and win in the moderate, educated and affluent suburbs.
Warner, who left office in 2006 with record high job-approval ratings, is strongly favored in his U.S. Senate race this year, and having him on the Virginia ballot can't hurt Obama.
But none of the Virginia Democratic triumphs came in a presidential election year, and things are different when the White House is on the line.
In the seven presidential elections since 1980, an average of 76 percent of the state's registered voters turned out. In the comparable seven gubernatorial elections, the average turnout has been 55 percent.
Republican-voting religious conservatives turn out heavily for presidential elections, partly to support candidates they believe will nominate Supreme Court justices hostile to abortion, gay rights and limits on school prayer.
Palin's addition to the ticket sent the signal those conservatives were looking for, said Ken Hutcheson, a veteran Republican strategist who has led numerous statewide campaigns, including Bush's 2004 re-election effort.
"Her nomination ensured they will come to the polls full force," Hutcheson said.
Virginia voters also found in Warner, Kaine and Webb a portfolio and a message more aligned to the state's moderate political tastes than Obama's.
"What often hurts the Democrats in Virginia is the national campaigns are focused more on the big swing states; Ohio, Pennsylvania and Michigan - with a message that hasn't been the best in Virginia," said Virginia Commonwealth University political scientist Robert D. Holsworth.
Obama still could defy the old electoral formulas. He has opened about 40 campaign offices across the state. His supporters have fanned out to register tens of thousands of new voters by the Oct. 6 deadline.
Registration drives, however, don't always translate into votes. Democrats led a voting drive that accounted for many of the 270,000 Virginia voters newly registered in 2004, but John Kerry lost Virginia by 9 percentage points.