Former president Bill Clinton brought his star power to Los Angeles this weekend, followed closely by Republican "Mama Grizzly"-in-chief Sarah Palin, who roused the faithful at a packed rally in Orange Country, south of LA.
The Republicans are fighting tooth and nail to help wrest power from the Democrats in crucial mid-term polls -- and also to elect another Republican to succeed former film star Arnold Schwarzenegger as California governor.
The most populous state in the United States and one of its most socially liberal, California has long been a Democratic stronghold, with a massive 61 percent of its voters backed Obama in the 2008 presidential polls.
But Congressional and gubernatorial races are more complicated, and the Republicans hope that gains in California can help them tip the balance nationally in Congress, two years after Obama won the White House.
"People know something has gone terribly wrong with our government," former vice-presidential candidate Palin told a packed and raucous rally in Anaheim -- a Republican bastion and home to Disneyland -- on Saturday.
"But people also know that there's nothing wrong in America that a good old fashioned election can't fix," added the former Alaska governor to wild applause from the 2,000-plus crowd of Republican and Tea Party fans.
The Clinton and Palin rallies -- and Obama's appearance in Los Angeles later this week -- are aimed at tipping the balance in favour of Republican and Democrat candidates running neck-and-neck, barely two weeks before polling day.
On the mid-term Congressional polls, all eyes in California are on incumbent Democratic Senator Barbara Boxer's struggle to hold off her Republican challenger Carly Fiorina.
Fiorina, a former boss of computer giant Hewlitt-Packard, has made up ground on Boxer but still lags behind her by 45 percent to 47 percent, according to the latest Real Clear Politics (RCP) poll-of-polls published by the LA Times.
In the race to succeed Schwarzenegger as governor, another Republican former hi tech company boss Meg Whitman, is running a close-fought race with her Democratic rival Jerry Brown.
The latest RCP poll puts 72-year-old Brown -- who was California governor from 1975-83 -- four points ahead of ex eBay chief executive Whitman, but the pair have swapped the lead in recent months, and there is all to play for.
On Friday night Clinton -- still one of the Democrats' biggest draws, nearly a decade after leaving the White House -- told students at UCLA that their votes could be crucial, as the Democrats battle to edge the Republicans out.
"I am pleading with you; you need to go out and tell everyone who is not here tonight that any college student in the state of California that doesn't vote in this election is committing malpractice on your own future," he said.
Earlier he had thrown his weight behind the local Democrat in another closely-watched race here -- between incumbent Congresswoman Loretta Sanchez and Vietnamese-origin Republican rival Van Tran in Orange County.
The stand-off has turned bitter after Hispanic Sanchez told a Spanish-language television station that "the Vietnamese" were trying to steal her seat, triggering charges of racism.
The Palin rally was specifically organised to back Tran -- who said he appreciated the publicity she could bring, even if he didn't have a chance to talk with her at length.
"She seems to be a very nice lady," he said.
"We didn't have a deep, thoughtful conversation because there were thousands of people there. "But I'm always happy to have any national figure come to town to excite the base and help with the turnout."
Palin became a global star after Republican John McCain made her his running mate in his doomed 2008 presidential bid -- and her fans hope she will win the Grand Old Party (GOP)'s nomination for the top job in two years' time.
"We want to elect Sarah Palin... because if not we'll get Barack Obama back," said 68-year-old John Poleshek, holding a banner reading "Palin for president 2012."
"And I figure we should start early. Two years is not a long time in political campaigns," he told AFP.
Obama, who will launch a four-day political campaign swing on Wednesday, is due to speak at the University of Southern California (USC) on Friday, 11 days before Californians join the rest of the country in voting to decide his party's fate for the next two years.
