She's been raising money for months, but Democrat Anna Caballero is making it "official" this week: she's running for the state Senate seat now held by Jeff Denham, R-Atwater, who terms out in 2010.

The oddly shaped 12th District runs from the Salinas Valley over to Merced, dropping into Madera. Caballero, who lives in Salinas, is trying to make the jump from the Assembly, where she's served a district that runs from the outskirts of San Jose to south of King City.

Caballero, an attorney and former mayor of Salinas, has scheduled kick-off events on Friday in Modesto, Merced and Hollister. So far she has the Democratic field to herself. The only Republican to file so far is Anthony Cannella, the mayor of Ceres and son of former Assembly Member Sal Cannella. He has raised $37,524 this year, according to the latest filings. Caballero raised $30,124.

The race could be among the most closely watched legislative contests because the 12th is considered one of the few swing districts in the state. The district was drawn for Democrats, who today hold a 48% to 33% registration edge. Denham pulled the upset in 2002, beating former Assembly Member Rusty Areias by just 1,843 votes.