The National Rifle Association has a new weapon in its bid to get more of its supporters elected to Congress. They're distributing political yard signs, a staple of First Amendment advocates. Signs reading "Don't Tread on My Gun Rights" are being provided to supporters to bolster local candidates who back the Second Amendment. Don't laugh. The NRA says yard signs can account for an extra 4 percent in votes on Election Day. "Think back to the 2000 presidential election, where 537 votes in Florida separated George W. Bush from Al Gore," says an NRA E-mail to supporters. "Four points seems like a landslide!"