No, it won't. Truthers, like any other grand conspiracy theorists, are self-sustaining. All evidence proves they're right, and any contradictory evidence or lack of evidence is simply the result of the grand conspiracy. Just like those who insist the moon landings were a hoax, Barack Obama is really a closet Muslim, George Bush planned 9/11, Kennedy's death couldn't be the result of an angry leftist, FDR was behind Pearl Harbor - they aren't looking for evidence. The verdict was already guilty. Like too much in modern scholarship (and boy do I use that term loosely), facts are incidental to what we already know to be true.
This also proves what our cultural narrative seeks to deny: that Leftists, progressives, and liberals are just as prone to have nuts, loons, crazies, and morons in their folds as the Right is able to produce. Are their nutty conservatives? Sure. But how can anyone listen to Joy Behar, Bill Maher, Rosie O'Donnell, or heck, Joe Biden and not realize that stupidity is in no way confined to a singular ideology.