DENVER (AP) -- A source in Dan Maes' campaign says the Republican gubernatorial candidate has picked former state Rep. Tambor Williams to be his running mate.

Williams is an attorney from Greeley who served four terms in the Colorado House. She was executive director of the Department of Regulatory Agencies under Republican Gov. Bill Owens.

The source didn't want to be identified because he wasn't authoritized to make the announcement.

Democratic candidate John Hickenlooper chose Colorado State University-Pueblo President Joe Garcia to be his running mate.

Doug Campbell is the running mate for American Constitution Party challenger Tom Tancredo.

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