It was widely reviled as a terrorist calling for Americans to vote against their president, George W. Bush, and instead strengthened the president's campaign. John Kerry would later contend that the video cost him the race. "It changed the entire dynamic of the last five days," Kerry said.
— Oct. 12, 2000: Al-Qaida in Yemen terrorists blow a hole in the USS Cole as it sits in port, killing 17 sailors.
The gut-wrenching shock to the nation didn't have a clear impact on the race between Gore and Bush. Later, a minor November surprise — the revelation that Bush had been arrested on a misdemeanor drunken driving charge back in 1976 — stirred Republican indignation because it came just five days before the election. Voters shrugged it off.
— Oct. 1, 1992: Billionaire Ross Perot, who had impulsively quit his third-party presidential bid in July, jumps back in.
Perot got a spot in the presidential debates alongside President George H.W. Bush and Clinton, leaving them scrambling to respond, and ended up siphoning votes from both sides.
"Sometimes it seems that we're at the mercy of events, instead of shaping events," Romney told supporters Thursday. He was referring to the United States and its role in the world.
The same could be said, however, of presidential campaigns.
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