And then there were 24.
President Obama will open four more offices in Virginia on Wednesday, bringing the total number in the swing state to 24.

President Obama greets people after arriving at Oakland International Airport on July 23. (By Susan Walsh/AP)

Romney’s campaign also has 24 offices, including nine that Gov. Bob McDonnell’s political action committee maintained after his election in 2009.

Both campaigns overlap in key areas: Northern Virginia, Hampton Roads, Richmond and Southside as well as Fredericksburg and Charlottesville. And both plan to open more offices.

Recent polls show Obama with a slight lead in Virginia, although most surveys rely on data that predate Romney’s clinching of the GOP nomination. A Washington Post poll in May had Obama ahead of Romney, 51 percent to 44 percent, among registered state voters.