(05-24) 21:30 PDT SAN FRANCISCO -- President Obama will land in the Bay Area today to raise money for U.S. Sen. Barbara Boxer's re-election campaign as an anti-incumbent wave has Republicans in blue California convinced this is their best shot in years to oust their liberal nemesis.

The president's two-day trip, which includes a pitch Wednesday for green jobs, underscores the high stakes for Democrats, who want to avoid a big loss this year in California, which could be a blow to the party in the 2012 presidential election.

At the same time, Republicans are eyeing Boxer's seat as a foothold toward recovering a majority in the Senate.

"It would be a huge coup for (Republicans) if they could win California, and a major breakthrough across a blue-state line," said Jack Citrin, a political science professor and director of the Institute of Governmental Studies at UC Berkeley.

Many Democratic Party insiders concede that Boxer, long viewed as "a cat with many lives," could be more vulnerable than other Democrats this year, including two-term Sen. Blanche Lincoln of Arkansas, who is also facing a contentious re-election bid, Citrin said.

Obama's trip to the Bay Area, a little more than a month after he traveled to Los Angeles for Boxer fundraisers, intends to help the three-term senator on two fronts: Today, he's expected to help raise $1.5 million, a possible record for a U.S. Senate campaign, in events at San Francisco's Fairmont Hotel.

On Wednesday, he'll head to Fremont to appear at an event at solar energy firm Solyndra Inc., where he will underscore green technology, an issue that Boxer holds as central to her role as the first woman to chair the Senate Environment and Public Works Committee.

"It's important to have the president in California as often as we can get him here," said leading Silicon Valley Democratic fundraiser Wade Randlett, who noted that Obama won California in 2008 with 61 percent of the vote.

"And if you have a race that's hard, you need to acknowledge that - and bring in the big guns to make it clear there's a real choice here."

Fight of Boxer's life

Obama's trip this week to San Francisco, one of the nation's most-liberal bastions and an ATM for Democratic Party fundraisers, is his second visit to the region since his election. In October, he raised more than $3 million for the Democratic National Committee at the St. Francis Hotel.

The visit comes as Boxer faces the fight of her life - no matter which of the three GOP candidates wins the June 8 primary.

Former Hewlett-Packard CEO Carly Fiorina, who is leading in the polls and has put $3.6 million of her own money into the race, would be the first woman to face Boxer.

Former South Bay Rep. Tom Campbell, who is running second behind Fiorina, is a moderate, pro-choice Republican - a challenge for Boxer in a solidly pro-choice state.

Assemblyman Chuck DeVore of Irvine is a conservative grassroots favorite who has doubled his support with the Tea Party wind at his back.

Boxer also faces a colorful longshot challenger in her own party - Slate.com political blogger Mickey Kaus, who is holding a "debate" today at a San Francisco hotel - whether Boxer shows or not.

He wants her to "debate the actual issues she's been avoiding in the primary, like her lockstep loyalty to organized labor, or support for illegal immigrant legalization."

Republicans say Obama's latest trip underscores the senator's vulnerability as well as his own.

"Rather than working to create jobs, California's junior senator ... would rather fund-raise," said Jahan Wilcox, a spokesman for the Republican National Committee. "And we're disappointed that the president isn't holding a town hall meeting in San Francisco. If he's going to pass the hat, he should meet with Californians on the unemployment situation."

Re-election a 'toss-up'

Some leading political handicappers classify Boxer's chances for re-election as a "toss-up" - decidedly weak in a state where Democrats outnumber Republicans by 44 percent to 30 percent, with 20 percent of voters declining to state a party affiliation.

But Democrats say none of Boxer's potential GOP challengers will be able to expect much financial help from their national party after June.

"I think (RNC Chairman) Michael Steele will try hard to make sure the money doesn't go all to bondage clubs," jokes Randlett, in a reference to a headline-grabbing recent GOP fundraiser at a Los Angeles adults-only club.

"It will be very hard for national Republicans to look at this race and decide a marginal dollar in the most expensive media market in the country is better spent here than it is going toward (Kentucky GOP primary winner) Rand Paul."

E-mail Carla Marinucci at cmarinucci@sfchronicle.com.

This article appeared on page A - 1 of the San Francisco Chronicle