SACRAMENTO — Democrats’ total dominance of the state Legislature likely comes down to a single state Senate seat in Tuesday’s election.

Republicans have held Senate District 12 for years, but incumbent Anthony Cannella can’t run again due to term limits.

Democrats were pinning their hopes on Assemblywoman Anna Caballero while Republicans fielded Madera County Supervisor Rob Poythress.

Dem Supermajority Within Reach

Democrats need 27 seats for a two-thirds majority in the 40-member Senate and had 26 heading into the election. The party is also working to defend its supermajority in the Assembly.

A supermajority would let Democrats raise taxes, suspend legislative rules or override vetoes without Republican votes.

That would be a benefit to Democrat Gavin Newsom, who polls showed leading in the governor’s race. If Republican John Cox wins, it could frustrate his efforts.

All 80 California state Assembly seats and half the Senate seats are up for election. But as a practical matter only a few could swing between the two major political parties as Democrats fan a backlash to President Donald Trump and Republicans rally opposition to last year’s gas and vehicle tax hikes that annually raise $5 billion to support transportation improvements.

18-Point Voter Registration Advantage

Though Cannella held Senate District 12 for eight years, Democrats are at an 18-point advantage in voter registration in the district that includes all or parts of Fresno, Madera, Merced, Monterey, San Benito and Stanislaus counties.

Supporters of Caballero, a former Salinas mayor, had to regroup on Election Day after someone broke into her campaign headquarters in Merced and took cellphones and computers used to contact voters, along with 10,000 pieces of campaign literature that volunteers were to hang on doorknobs.

Campaign spokesman Bob Sanders said the thief left behind televisions and a microwave oven. Campaign volunteers were delayed several hours but were still able to reach targeted voters, he said.

Poythress condemned the break-in in a statement saying that campaigns should be run and won on the issues.

Caballero lost to Cannella in 2010 in the mostly rural farming district, and Republicans are emphasizing her support last year for higher gas and car fees.

Republicans Confident in Other Races

Republicans are more confident of retaining challenged seats held by incumbent Sens. Andy Vidak in neighboring Senate District 14 and Janet Nguyen in the predominantly Orange County-based Senate District 34, despite Democrats hope for a backlash to President Donald Trump.

Democrats are considered likely to retain their two-thirds supermajority in the 80-member Assembly, where they need 54 votes and have had 55. Republicans already gave up another vote when voters picked two Democrats to face off for the seat vacated by incumbent GOP Assemblyman Rocky Chavez.

Republicans are targeting Riverside County Assemblywoman Sabrina Cervantes and several other Democrats representing inland suburban commuter districts for supporting higher gas taxes.

The parties are fighting what Assembly Republicans political director George Andrews called a “money war” over Cervantes’ seat, as well as trying to capitalize on weak primary election support for Democratic Assemblyman Rudy Salas of Bakersfield.