In a July 9th speech in South Park, PA, McCain criticized Obama's voting record regarding the Iranian Revolutionary guard, and their recent missile tests:
"It's my understanding that this missile test was conducted by the Iranian Revolutionary Guard. This is the same organization that I voted to condemn as a terrorist organization when an amendment was on the floor of the United States Senate. Senator Obama refused to vote."
He's referring to the September 26th, 2007 vote on the Kyl-Lieberman Amendment. He was correct in stating that Obama "refused" to vote on it. The problem is that McCain didn't vote on it, either. The US Senate web site lists both senators as having not voted on the measure.
Now, the CNN article says that the McCain campaign "admitted the error;" however, as of July 22nd (thirteen days after the error was made), the quote is still at the very top of the transcript of that speech, and there is no clarification that McCain's claim that he voted to pass that amendment was patently false.