Maryland residents can now register online to vote using a new Web-based system. The Maryland State Board of Elections began promoting its new online-registration system with tweets from Gov. Martin O’Malley on Tuesday. The system has been available since July 9 and had been in the works for longer than a year. “It’s been on our radar screen for a while,” said Mary Cramer Wagner, director of voter registration for the state board. “You always want the next best thing.” People wanting to vote enter their personal information and driver’s license or state-issued ID numbers on a website. The license and ID numbers are cross-referenced with the Motor Vehicle Administration (MVA) to ensure validity. Military members stationed overseas can register online to vote using the last four digits of their Social Security number instead. If a resident doesn’t have a driver’s license or state-issued ID and is not actively serving overseas, he or she still needs to sign and send in a voter-registration application. Residents required to mail applications can use the new website to fill them out before printing them.