Sept. 16, 2008 -- Democrat Barack Obama goes from wooing voters in a Denver suburb in the swing state of Colorado today to rubbing shoulders with Hollywood A-listers tonight at a big-money Beverly Hills fundraiser featuring mega-star Barbra Streisand.
Dreamworks' Steven Spielberg, Jeffrey Katzenberg and David Geffen are co-hosting tonight's party -- a reception and dinner costing $28,500 a person at Los Angeles' Beverly Wilshire Hotel, followed by a later event featuring Streisand at $2,500 a ticket.
Sen. John McCain blasted Obama Tuesday for the Hollywood fundraiser.
"He says he's siding with the people just before he flew off for a fundraiser in Hollywood with Barbra Streisand," McCain said in Vienna, Ohio.
"Let me tell you my friends, there's no place I'd rather be than right here with the working men and women of Ohio."
The Beverly Hills soiree is the latest fundraiser Obama must attend between now and Election Day -- many of them taking him off the trail to states like California and New York, where he is likely to win in November.
Obama recently attended a Sept. 5 fundraiser at the home of musician Jon Bon Jovi in New Jersey.
As he competes for votes in the next 49 days, the Illinois senator must simultaneously try to replenish his war chest to compete financially with his Republican rival, McCain, who decided to accept $84 million in public financing.
Obama made the unprecedented decision to abandon his earlier pledge to accept public funds and must now work overtime to keep the money flowing in.
"This is the first time any major presidential candidate in the modern era has rejected public financing in the general election," said political science professor Costas Panagopoulos, director of the elections and campaign management department at Fordham University.
Panagopoulos said, while there may be advantages for Obama's decision to raise campaign money himself, the disadvantages are clearer.
"One advantage may be that Sen. Obama raises substantially more money than he would have if he accepted public financing, but the fact remains that he will have to devote considerable time to fundraising in the general election and that [his] opponent will not," Panagopoulos said.
"That time spent fundraising might take time away from voter outreach and other activities that are necessary for presidential candidates to campaign across the country in a relatively short period of time."
Both candidates are filling the airwaves in battleground states with expensive media ad buys that are making a dent in their campaign war chests.
"At this point in the campaign, the candidates are spending in excess of about $1.4 million a day on TV ads, and this is not even the most that they will be spending," said Evan Tracey, CEO of TMS' Campaign Media Analysis Group.
Candidates Spend Millions on TV Ads in Battleground States
Tracey said some of the 10 to 14 key battleground and swing states have some of the most expensive media markets in the country.
Obama, who has had unprecedented success tapping into millions of small donors online, has raised more money than any presidential candidate in election campaign history -- raising a record-breaking $66 million in August alone.
McCain, whose presidential campaign was floundering financially a year ago, raised $47 million in August, a personal best for his White House bid.
After the recent conventions, McCain was capped at spending the $84 million in taxpayer funds allotted to him under the public financing system.
But the Arizona senator is getting help from the Republican National Committee, which has, so far, taken in $109 million more than the Democratic National Committee in fundraising money, according to Federal Election Commission documents.
Since 2007, the RNC brought in $219.2 million and spent $147.2 million, while the DNC brought in $109.8 million and spent $105.8 million.
Senate Majority Leader Harry Reid, D-Nev., made a personal appeal to Obama earlier this month, asking him to share some of his wealth to get senators re-elected, but Obama declined.
The Obama campaign so far has agreed only to let Senate Democrats use Barack and Michelle Obama and vice presidential candidate Sen. Joe Biden, D-Dela., in online appeals and direct mailers. Obama hasn't held joint fundraising events with House or Senate Democrats.
Meanwhile, Republicans are bragging about a surge in fundraising, following McCain's selection of Alaska Gov. Sarah Palin to join the Republican ticket.
"She's re-energized the base," Republican lawyer Ben Ginsberg told ABCNews.com recently, arguing Palin has helped the GOP raise a significant amount of money.
The Republican National Committee reported taking in $1 million after Palin's acceptance speech at the convention, although the Obama campaign reported taking in $10 million.
Palin's selection has appeared to energize A-list celebrities in Hollywood, with actor Matt Damon saying her pick is "like a really bad Disney movie" and Streisand criticizing McCain's selection of Palin on her Web site.
Streisand originally backed Obama's primary rival Sen. Hillary Rodham Clinton, D-N.Y. But Streisand switched to support Obama when he clinched the Democratic presidential nomination.
"This calculated, cynical ploy to pull away a small percentage of Hillary's women voters from Barack Obama will not work," Streisand wrote on her Web page. "We are not that stupid!
"I believe John McCain chose Gov. Palin because he truly believes that women who supported Hillary, an experienced, brilliant, lifelong public servant, would vote for him because his vice president has two X chromosomes," Streisand said. "McCain's selection of Gov. Palin is a transparent and irresponsible decision, all in the name of trying to win this election."
ABC News' Tahman Bradley contributed to this report.