Though a tradition support base for Democrat candidates, Republican presidential hopefuls also eye the state for support.
Republican candidates are set to kick off a week of intense presidential campaigning in Southern California, with Republican front-runner Rudy Giuliani scheduled to make appearance on Sunday.
Meanwhile, Democrat Bill Richardson is also scheduled to speak to the public to counter the republican rivalry.
Giuliani will speak at the Republican Party of Orange County's annual Flag Day Dinner in Irvine, with more than 1,000 people expected to attend the 250-dollar per person event, a party official said.
At least 30 Republicans critical of the former New York City mayor's support of the right of a woman to have an abortion, gay rights and gun control are expected to protest outside the Hyatt Regency Irvine, according to Ken Fisher, the president of the Anaheim Republican Assembly and an organizer of the protest.
Despite the criticism from some Republicans, the Giuliani campaign is "very happy with where we stand in the polls and the support we are getting at all levels in California," an aide said.
"Mayor Giuliani continues to be the leading Republican choice in California," Jarrod Agen said. "California is going to be a state where we can win in the primary and Mayor Giuliani is the one Republican who can put California in play in the general election as well."
In the most recent Field Poll of California Republicans' presidential preferences, Giuliani was first with 29 percent, with Arizona Sen. John McCain second with 21 percent. No other candidate received 10 percent or more.
Former Tennessee Sen. Fred Thompson, who is expected to formally declare his candidacy next month, and former House Speaker Newt Gingrich, who has said he hasn't decided if he will run, were both included in the poll, conducted between March 21-31.
The poll of 315 likely Republican primary voters has a margin of error 5.8 percentage points.
Giuliani also will attend a pair of fund-raisers tomorrow in his fourth visit of the year to Orange County, Agen said.
Richardson, New Mexico's governor, will begin two days of fund- raising with afternoon and evening events in Los Angeles, an aide said.
On Monday, Illinois Democratic Sen. Barack Obama will start two days of Southern California fund-raisers. Meanwhile, former Massachusetts Governor. Mitt Romney will be in Riverside County for a series of events in his bid for the Republican nomination, and Thompson will be in Burbank to appear on "The Tonight Show with Jay Leno."
McCain is also expected to attend a fund-raiser reception in Southern California next week.