BOSTON (CBS) –It might just be the biggest upset of the NCAA tournament.

Mitt Romney, the former Massachusetts governor and 2012 Republican nominee for president, has never claimed to be an expert on basketball. But his March Madness bracket turned out to be one of the most accurate in the country, finishing in the 99.9th percentile.

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Romney correctly picked Duke as the national champion, nailed the Final Four and selected six of the Elite Eight teams. His bracket was leaked by a source to the Huffington Post.

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In 2012, Romney said he decided not to fill out a bracket because he was too busy campaigning. Now he just wishes he put some money on his picks.

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“Should’ve put $10,000 on my bracket,” Romney tweeted after the championship game, referencing a widely-mocked remark during a 2011 presidential primary debate. “Congrats, Coach K and @DukeU.”