Obama In LA May 10, 2012: George Clooney's Studio City Bash Could Lead To 'Starmageddon' (VIDEO)

George Clooney's fundraising dinner for President Barack Obama is turning out to be so much more than expected.

For one, the dinner is now expected to raise close to $15 million -- not the originally reported $12 million, which was already a record-breaking amount for any presidential fundraiser in the U.S.

Here's the breakdown: $6 million is coming from 150 high-wattage Hollywood guests who paid $40,000 per ticket to be there tonight. The rest, about $9 million, comes from small donations across the country as part of a sweepstakes the campaign held. Two lucky winners from that pool (and two guests) were selected to dine at the head table with the President and Clooney, and their names will be announced tonight.

Secondly, now that the President has come out about his personal support for gay marriage, this dinner will probably turn into a par-tay. People in the entertainment industry have long been faithful supporters of gay rights and marriage equality, and some guests who will be attending either have ties to activist causes or are a noteable part of gay Hollywood.

Invited guests include Barbra Streisand, who once hosted a major fundraiser to defeat Prop 8 in 2008, and actor Robert Downey Jr., who has pushed the envelope in the past by insinuating that his character in the "Sherlock Holmes" franchise could be gay. CAA partner Bryan Lourd is a towering figure in gay Hollywood (he left his three-year relationship with Carrie Fisher to be with another man), and he's expected be at the event as well.

Other guests include actor Tobey Maguire, producer J.J. Abrams and ICM president Chris Silbermann, according to Obama Foodorama.

Now for the little people. While a lucky few are busy prepping and primping for the big event tonight, Valley and Hollywood Hills residents are getting ready for "Starmageddon." Here's what we know so far, via a letter from Councilman Paul Krekorian

• After spending the first part of the day in Seattle, Wash., President Obama is scheduled to arrive at LAX at around 6 p.m. The President will be transported via helicopter and motorcade to George Clooney's home.
• Alert to residents in the hills: neighborhood street closures and emergency vehicles could result in limited delays.
• Alert to commuters: if you're driving on Laurel Canyon Boulevard and connecting streets north of Ventura, expect delays and road closures from 5 p.m. to 8 p.m.
• Alert to Studio City residents: local access to the area south of Ventura Boulevard in Studio City will be "virtually sealed off" from 8 p.m. to 10 p.m., according to the LAPD. Only local residents with a current photo ID that displays their home address will be allowed to get through.
• Alert for George Clooney's neighbors: People who live in and around Fryman Canyon should either stay home or make other arrangements during the event. Everyone else should stay out!
• President Obama is staying the night in Beverly Hills and leaving Los Angeles in the early morning, as usual.

Barring the warning about neighborhood street closures in "the hills," here's a visual approximation of Councilman Krekorian's advice about possible street closures.

View Streets That Could Be Impacted By President Obama's Visit On Thursday, May 10 2012 in a larger map

It looks like it could be a nasty commute tonight for people crossing the canyons, so good luck out there!