After years of posturing and threats, the Chargers could be on the move.

Voters in San Diego County on Tuesday soundly rejected a referendum that would have steered hundreds of millions of tax dollars toward a stadium the team wanted to build in downtown San Diego.

The Chargers must decide whether to pay for the stadium themselves, look for an alternative site elsewhere in the city for a stadium, or move to Los Angeles, where they have an option to move into a stadium being built by Stanley E. Kroenke, the owner of the Rams.

The Chargers, who have several years left on their lease at Qualcomm Stadium, have until the second week of January to exercise that last option. If the team’s owner, Dean A. Spanos, decides not to move the Chargers to Los Angeles, the Oakland Raiders will then be given the option to join hands with Kroenke.

“In terms of what comes next for the Chargers, it’s just too early to give you an answer,” Spanos said in a statement. “We are going to diligently explore and weigh our options, and do what is needed to maintain our options, but no decision will be announced until after the football season concludes, and no decision will be made in haste.”