This is an excellent example of a really, really funny prank that also happens to have a positive social message on a number of fronts. Here's the scoop, via Michael Arrington at TechCrunch, who explains how someone could just hack into a presidential candidate's MySpace page:
Someone on Presidential hopeful John McCain's staff is going to be in trouble today. They used a well known template to create his Myspace page. The template was designed by Newsvine Founder and CEO Mike Davidson (original template is here). Davidson gave the template code away to anyone who wanted to use it, but asked that he be given credit when it was used, and told users to host their own image files.
McCain's staff used his template, but didn't give Davidson credit. Worse, he says, they use images that are on his server, meaning he has to pay for the bandwidth used from page views on McCain's site.
Davidson decided to send a strongly-worded letter requesting the proper credit. Just kidding! Actually, he tinkered with one of the images on his site that they were accessing, and replaced the "contact information" box with this statement:
Today I announce that I have reversed my position and come out in full support of gay marriage...particularly marriage between two passionate females.
Who wants to bet that McCain just rocketed up in the polls? Davidson did McCain a favor! Not to mention making an important political statement about gay rights, and intellectual property rights, and the rights of hot ladies to love each other. McCain and his staffers maybe don't see it that way, because they've already scrubbed the image, but Arrington and Newsvine (which also explains why what McCain and his MySpace-makers did was a no-no) have it preserved for posterity, as does every site that is now picking it up. Gotta love the internet, eh, presidential candidates?