As Melgamatic said Romney has signed and endorsed numerous anti-2nd amendment bills/laws. Obama hasn't done anything to weaken the 2nd amendment that I've seen. This is bound to get moved to politics anyway so before that happens, all I am going to say is read about how much support Ron Paul has. If you just watch mainstream media you would assume Dr. Paul wasn't even in the race any longer. But yet all his rallies are packed with supporters despite the media blackout.
I would bet money that either four more years of Obama or 4 years of Romney, and are country will be in same condition or more then likely, worse.