Giving an enormous bump to the San Francisco mayor and candidate for Governor of California in the 2010 race to succeed term-limited Republican Arnold Schwazenegger, former President Bill Clinton has thrown his support behind Gavin Newsom, who currently trails primary opponent, current Attorney General, and former Governor Jerry Brown in both polling and funds raised.

The relationship between Newsom, Brown, and Clinton is a rich one.  Back in 1992, it was Jerry Brown who was Clinton's biggest opponent in the early stages of the primary race for the Democratic presidential nomination (though it ultimately came down to Clinton and Paul Tsongas).  And it was Brown who opened the door for one of those famous Clinton moments:

Clinton went on to famously tell Brown that he wasn't "fit to share the stage" with his wife.  Fifteen years later, when superdelegates were lining up behind either Hillary Clinton or Barack Obama, Brown (probably wisely) stayed out of the fracas altogether.  But even that wasn't without its difficulties.  Despite their electoral differences, Brown and Clinton were both members of the Democratic Governors Association, and Hillary advisor Ace Smith was Brown's top campaign chief for much of his political comeback over the past 10 years.

Enter Newsom.  When the fresh faced mayor of the most liberal city in the country decided to choose sides, he backed Hillary, even as polling numbers and the superdelegate count were showing Obama well ahead of the former First Lady.  Since Obama has taken office, Bill Clinton has spent considerable time stumping for candidates who stuck their necks out for his wife.  And Newsom was one of the big ones.

The Clinton endorsement will help Newsom tremendously.  Bill Clinton is a political animal, but understand how rare it is for a former president to offer primary endorsements in a gubernatorial race two thousand miles away from his home state of Arkansas (three thousand if you're counting from his new home in New York).

Still, Newsom faces an uphill battle against a man whose name has been a fixture in California politics for the last 60 years, and in San Francisco for the last 70.  His father, Pat Brown, was elected District Attorney of San Francisco in 1943, became Attorney General in 1951, and finally Governor of California in 1959.  Jerry was elected Secretary of State in 1971, and served as Governor from 1978 to 1983.  After a 15 year hiatus, he was elected Mayor of the troubled City of Oakland in 1999, and won the widest margin of any statewide candidate when he ran for Attorney General in 2006.  Though California imposed term limits on its Governor in the late 1970s, Brown- whose terms were begun prior to the term limit legislation- is grandfathered in.

Brown has an unparalelled name recognition in the state, and it's likely that polling now- 14 months away from election day- reflect that.  Newsom is known outside of the Bay Area perhaps as much for his personal life than his professional one.  But as the campaigns heat up in the spring of 2010, those polls may equal out on their own.  The Clinton endorsement will help with that.

More importantly, Brown's well-established statewide fundraising network is booming, while Newsom is still working to establish one.  Again, Clinton's word will help bring in some of the former president's donors, and may cut Brown's advantage considerably.

The winner of the primary will face off against either of two Republicans running to succeed Arnold: state Insurance Commissioner Steve Poizner, and former eBay President and CEO- not to mention notable McCain backer- Meg Whitman.