FILE - In this April 30, 2012 file photo, President Barack Obama speaks in Washington. It's on. Independent groups favoring Mitt Romney are launching TV advertisements in competitive states, providing cover against President Barack Obama's well-heeled campaign. Romney advisers also are wooing wealthy patrons of former GOP rivals. It all underscores how federal court cases _ including Citizens United _ have paved the way for a flood of campaign cash from corporations and tycoons looking to help their favored candidates. (AP Photo/Evan Vucci, File)