San Diego Mayor Jerry Sanders, facing a June 3 primary challenge from fellow Republican Steve Francis, has won the endorsement of the San Diego Union Tribune.

“The question for voters on June 3 is whether Sanders is making enough progress to merit a second term. The answer, in our view, is an unhesitating Yes,” the paper said.

The Union Tribune is the largest newspaper in the city, with a circulation of 296,000.

Sanders, who is a former chief in the San Diego Police Department, is running for his second term after entering the mayor’s office in 2005.