Story highlights He was expected to run against Keith Ellison

He says he has other priorities

Washington (CNN) Howard Dean has dropped his bid for a second stint chairing the Democratic National Committee, citing "other priorities" and a "possibly divisive" race.

"I'm not going to be a candidate for the DNC chairmanship," the former Vermont governor and 2004 presidential candidate said at the start of an Association of State Democratic Chairs forum in Denver. "I think it could possibly be divisive. I have other priorities. I have a grandchild now. But I am fully dedicated to using as much time as I can to support whoever the chairman is."

A leading contender for the spot is Rep. Keith Ellison of Minnesota, who is still in the running for the position despite criticism over his past ties to the Nation of Islam and his defense of its leader, Louis Farrakhan, resurfacing in the news this week. Ellison distanced himself from the group during his first congressional run a decade ago.

Dean served as the governor of Vermont from 1991 to 2003 and gained a national following during his bid for 2004 Democratic nomination by drawing support online -- a fairly novel concept at the time -- which came up short. Dean then in early 2005 won a spirited contest to chair the DNC. During his tenure Democrats won control of the House in 2006, and Barack Obama won the presidency two years later.

Dean earlier this month threw his hat in the ring for the reprise of that role, and was expected to be among Ellison's most formidable challengers.

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