Wonkette says this campaign ad for GOP front-runner Sen. John McCain will start playing locally now that the “Potomac Primary” on Feb. 12, made up of Maryland, D.C. and Virginia, is one of the next big strategic primary dates on the calendar. Below is the one of the two ads Sen. Barack Obama is now running in Maryland. UPDATE: This video is running in Maryland, according to Obama’s campaign web site linked previously. But…