Bill Christiansen, a former Tulsa city councilor and mayoral candidate, announced he's endorsing former Tulsa Mayor Kathy Taylor.
Christiansen, a Republican, received 23 percent of the vote in the June 11, 2013, non-partisan primary, finishing third behind fellow Republican Mayor Dewey Bartlett and Democrat Kathy Taylor.
Voters will decide between Taylor and Bartlett on November 12.
Christiansen, who owns Christiansen Aviation, represented District 8 on the city council for five terms.
He made the announcement during a news conference Wednesday afternoon.