That's the appetizer for the main event. Clinton has also agreed to host a fundraiser to benefit Newsom's campaign. It's not clear which Newsom needs more: the flashy endorsement or the money. He's behind on both fronts, and in the polls, too.
In the money race, Newsom's campaign is trailing State Attorney General and former governor Jerry Brown, who has outraised Newsom by a seven to one margin.
Many political insiders see this as a make-or-break week for the San Francisco mayor.
The San Francisco Chronicle noted it isn't helping that DreamWorks titans Steven Spielberg and Jeffrey Katzenberg have announced an LA fundraiser for Brown.
When news of the Clinton endorsement was made public last month, Newsom said he was honored to have the former president's endorsement and he thinks it is a "significant thing for our campaign."
"I couldn't be more proud and honored to have my boy!" Newsom said at the time.
The casual reference points to the relationship between the two. Their political relationship goes back to Newsom's mayoral campaign, which Clinton also supported.
The move is not that big of a surprise when you consider Newsom's pit bull-like support of Hillary Clinton during her recent unsuccessful race for the White House. He was one of her biggest supporters.
California's had a thing for Bill Clinton ever since he beat Jerry Brown in the 1992 presidential primary. He recieved rock star-like receptions here, even in the height of the Monica Lewinsky scandal.
A recent poll by David Binder shows Brown leading Newsom, even among San Franciscans, 51 percent to 34 percent. And again, that is even before Brown has even officially announced he's running.
Newsom blamed his low poll numbers because he said he doesn't have the name recognition Brown does. He says that means he needs to work harder and smarter.
Each of them hopes to succeed Gov. Arnold Schwarzenegger, who will be termed out of office in November 2010.