Story highlights Harrison was a distant contender

Both Perez and Ellison within striking distance of the majority

Atlanta (CNN) Tom Perez moved closer to clinching the race to chair the Democratic Party after one of his competitors dropped out and endorsed the former labor secretary -- shaking up the contest two days before the election.

South Carolina Democratic Party chairman Jaime Harrison emailed Democratic National Committee members Thursday to say he is dropping out and backing Perez.

Harrison was a distant contender -- far behind Perez and Minnesota Rep. Keith Ellison. "In a former job, I whipped votes for House Democrats. I know what a path to victory looks like," Harrison said in his email, acknowledging he couldn't win.

But with both Perez and Ellison within striking distance of the majority of the DNC's 447 voting members, Harrison's support could push Perez over the edge -- and make Harrison the kingmaker.

Vote-counting is nebulous, since some DNC members have not revealed their plans even privately, and there's no reason those who have committed to support one candidate couldn't change their minds at the last minute.

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