White House hopefuls Sen. Hillary Clinton (D-N.Y.), former Sen. John Edwards and New Mexico Gov. Bill Richardson again courted support in Hollywood over the weekend, racing to raise cash and line up endorsements in advance of a March 31 deadline.

The biggest event was Clinton’s gala at the sprawling Beverly Hills estate of supermarket magnate Ron Burkle. That star-studded affair drew some 700 people and raised around $2.6 million.

Sen. Barack Obama (D-Ill.) raised some $1.3 million at a $2,300-per-person cocktail reception last month hosted by David Geffen, Steven Spielberg and Jeffrey Katzenberg.

Clinton and Obama, the two superstars in the race for the Democratic nomination, have drawn an enormous amount of attention as they try to line up support among high-profile donors in Hollywood and elsewhere.

At Burkle’s home, where guests dined in a tented lawn and ate a dinner of chicken and mashed potatoes, Clinton was introduced by Mary Steenburgen, a longtime friend and supporter. Organizers played a song that Merle Haggard recorded, “Let’s Put a Woman in Charge,” and much was made of the fact that the country singer has supported GOP candidates in the past.

“It was a spectacular event,” said Noah Mamet, a Los Angeles political and fund-raising consultant who was a co-chair of the fete. “Many people who were there have gone to many events Burkle has hosted, but this will go down as one of the more memorable. There was a real feeling at the end that she is going to be the next president of the United States.”

In her 15-minute speech and 20 minutes of Q&A, Clinton talked about a wide range of issues including health care, the environment, the war in Iraq, as well as balancing the budget and other “things she would do as president,” said Sim Farar, one of the chairs of the event along with his wife, Debra; Haim and Cheryl Saban; Steve Bing; Burkle; and Daphna and Richard Ziman.

Also present were Barbra Streisand and her husband, James Brolin, both seated next to Clinton. Streisand asked the first question during the Q&A and, when handed the mic, quipped, “I don’t like microphones.”

Later, John Emerson, chairman of the Los Angeles Music Center, asked Clinton what her husband’s role would be if she was elected. Given that there’s no precedent for a first husband, she said she would figure it out when the time comes.

Attorney Tom Girardi, who backed Edwards in 2004, sat at a table with Burkle and Bing. Other attendees included Steenburgen’s husband, Ted Danson; Warner Bros.’ Alan Horn; Yahoo’s Terry Semel; Semel’s former Warner Bros. colleague Bob Daly and his wife, Carole Bayer Sager; “Entourage” star Jeremy Piven; producer Bruce Cohen; music exec Clarence Avant; HBO’s Chris Albrecht; Motown’s Berry Gordy; Frank Biondi; Norman Lear; Ticketmaster’s Fred Rosen; Paula Abdul; and Christine Lahti.

Tickets cost $2,300 per person for the dinner and $4,600 per person for a pre-dinner VIP reception, at which Clinton posed for individual photos with the 250 or so people there. Although federal election laws limit contributions for the primary race to $2,300 per person, they also allow Clinton and other candidates to concurrently raise up to $2,300 per person for the general election as well.

Organizers prepped for the event for almost two months, with Clinton herself visiting Los Angeles twice to meet with donors ahead of the gala. Organizers already are making plans for further events in April, including one to be co-hosted by Spielberg, who has yet to make a formal endorsement in the presidential race.

Candidates are on a mission to raise as much money as possible before the Federal Election Commission’s first-quarter reporting period ends on Saturday. By April 15, each campaign must make public its fund-raising figures and totals, and the results will be an early indicator of each candidate’s strength in the race.

In fact, Bill Clinton, who was not present at Saturday’s event, appeared in a video on his wife’s Web site over the weekend, urging donors to contribute in advance of the deadline. But campaigns are also trying to minimize expectations. Sen. John McCain (R-Ariz.) warned that his totals will fall short of goals because of what he called a late start in raising money.

On Friday, Edwards attended a fund-raiser at the Santa Monica home of Skip Brittenham and Heather Thomas that one attendee said had the feel of a town-hall forum. Edwards has been to Los Angeles several times to raise money at medium-sized gatherings from an array of industry figures.

Among those present were Laurie David, Cindy Horn, Lear, James L. Brooks, Nina Jacobson, Armyan Bernstein, Skip Paul and J.C. Spink. Edie Wasserman was there as well, along with her daughter Lynne and granddaughter Carol Leif.

With Edwards was his wife, Elizabeth, who announced a day earlier that her cancer had returned. Before her husband spoke, she talked of meeting many people on the campaign trail who faced health crises like her own but lacked adequate health care coverage and held minimum wage jobs. Then, speaking for about 45 minutes, John Edwards addressed topics ranging from global warming to U.S. foreign policy.

Richardson was in L.A. for several days, attending a reception Thursday at the offices of agent Mitch Kaplan. On Saturday, he was the keynote speaker at the Human Rights Campaign, where he called for an end to the military’s “Don’t ask, don’t tell” policy and pledged that if elected, he would make AIDS funding “the highest priority.” He said he would appoint his vice president to be the chairman of an AIDS commission.

Noting his record, as well as a recent trip to Darfur in which he helped negotiate a cease fire in the war-torn region, Richardson said, “You have to ask, ‘Do they talk the talk or walk the walk? Can you get things done?”

Outside Burkle’s estate, Clinton’s event did draw some protesters from Codepink: Women for Peace. Among other things, they have been highly critical of Clinton’s 2002 vote in favor of a bill that authorized President Bush’s use of force in Iraq. Inside, according to one source, Clinton talked of an “organized” end to the war.

There will be more presidential politicking this week as Sen. Christopher Dodd (D-Conn.) attends a fund-raiser on Thursday at the home of producer Tom Werner, who co-hosts with Ron Meyer and Russell Goldsmith. On the other side of the aisle, former Massachusetts Gov. Mitt Romney will attend a Tuesday fund-raiser hosted by developer Rick Caruso.