There will be a runoff in November between Pleasant Hill City Councilmember Ken Carlson and BART director Debora Allen to replace retiring Karen Mitchoff on the Contra Costa County Board of Supervisors.

Carlon finished first in Tuesday’s primary election, garnering nearly 28 percent of the vote. Allen finished second, with 25.6 percent, according to unofficial results.

Concord City Councilmember Carlyn Obringer finished third, with 24 percent. Carrillo Garza, a former public health program manager for Contra Costa Health Services, finished fourth with about 13 percent, followed by Concord City Council Member Edi Birsan with a little more than 9 percent.

District 4 includes parts of Walnut Creek, Pleasant Hill, Concord, and Clayton. As the top two finishers in a race in which no candidate finished with more than 50 percent of the vote, Carlson and Allen earned the right to face off in the November election.