John Warner, a former United States Under Secretary of the Navy, had served Virginia in the Senate since 1979, and had been cagey about whether he would be running for re-election.

When Warner reported on April 12, 2007, that he had raised only $500 in campaign contributions during the first quarter, speculation increased that he may not seek a sixth term.

[3] The race was expected to be competitive, given the Democrats' two successive gubernatorial victories (2001, 2005) and the unseating of Republican senator George Allen by Jim Webb in 2006.

[8] On October 13, the Republican Party of Virginia's State Central Committee voted 47–37 to hold a statewide convention rather than a primary.

[11] On January 7, 2008, Delegate Bob Marshall (R-Prince William County), a sixteen-year state legislator from Northern Virginia known for his social conservative values, announced he would challenge Gilmore for the Republican nomination May 31, 2008.

Mark Warner later won election in 2001 as Governor of Virginia, and left office with a high level of popularity in 2006.

Glenda Gail Parker from Alexandria, a retired U.S. Air Force officer, ran again for the Independent Greens as she did in the 2006 Senate election.

[17] After the conclusions of the state conventions, Democrat Mark Warner had emerged as the front-runner for the Class 2 Senate seat from Virginia.

Pundits and analysists believed Virginia to be the single strongest pickup opportunity for the Democrats due to Warner's consistent lead in the polls.

On October 6, 2008, Mark Warner and Jim Gilmore debated various issues, including the Emergency Economic Stabilization Act of 2008, the Iraq War and Judicial nominees.

The Richmond Times Dispatch sponsored the debate held at the Taubman Museum of Art, Roanoke, Virginia.