Rich Gordon, a three-term San Mateo County Supervisor and Assemblyman-elect, announced his endorsement of Dave Pine for the San Mateo County Board of Supervisors.

Gordon added his name to a list of more than 100 Pine supporters, including council members, school board members, and environmental leaders from throughout the county.

"I'm thrilled to have Rich's support," said Pine, who serves as the San Mateo Union High School District Board President. "I have great respect for Rich and the work he's done in the public sector."

A seat on the board will open in Spring 2011 following the resignation of Mark Church, who becomes San Mateo's assessor-clerk-recorder in January.

Pine said the election will take place in the spring, most likely sometime between mid-March and mid-April.

"To have [Gordon's] endorsement means a lot," Pine said. "I think he's a role model for the way people should conduct themselves in public life."

The passage of Measure U earlier this month, which amended the procedure for filling vacancies on the board, necessitates an election to fill the position, although it may be conducted entirely through mail-in ballots.

Measure U dictates that if a vacancy occurs on or before Oct. 15 of the term's third year, an election is required to fill the position. If the vacancy occurs after Oct. 15, it can be filled by election or appointment.

Burlingame Vice Mayor Terry Nagel, Millbrae City Council Member Gina Papan and San Mateo County Community College District Trustee Richard Holober join Pine in the race.