A legal battle over the downtown arena may get a little crowded.

Mayor Kevin Johnson's political group "The 4000," Sen. Darrell Steinberg and the Kings say they all want a say in a new lawsuit against the City of Sacramento filed by STOP.

Two groups are suing now that the city clerk has rejected petitions to get a subsidy plan on the ballot and the arena supporters say they want to intervene.

The 4000 would help with arguments, Steinberg has an interest since he's penned legislation to streamline construction, and the team says it has already spent $45 million on the project -- including $36 million for the land at downtown plaza.

 PHOTOS: Downtown Arena Drawings