(CNN) - Call it a belated birthday gift for Jerry Brown.
A new poll in California indicates that the Golden State governor's approval rating is soaring and that he's far ahead of his Republican challengers as he runs this year for an unprecedented fourth term in office. The Wednesday release of the Field Poll comes two days after Brown turned 76.
According to the survey, 59% of California voters approve of the job Brown's doing in Sacramento, his highest approval rating since returning to the governor's office at the start of 2011. Only 32% give Brown a thumbs down on his performance as governor.
The poll also indicates that 57% of likely voters in the state's June open primary back Brown, far ahead of any of the Democrat's three GOP challengers. Assemblyman Tim Donnelly's at 17%, with Laguna Hills Mayor Andrew Blount at 3% and former U.S. Treasury official Neel Kashkari at 2%. The top two finishers in the June primary, regardless of their political party, will face off in November's general election.
Brown served as California governor from 1974-1982, Oakland mayor from 1998-2006, California attorney general from 2006-2010, and was elected governor again four years ago.
In January, the governor said he wouldn't make another bid for the White House in 2016. Brown first ran for president in 1976 at age 38, winning a couple of primaries over eventual Democratic nominee Jimmy Carter. He ran again four years later, finishing far behind Carter and Sen. Ted Kennedy. In 1992, he launched a third campaign for the White House, winning a bunch of primaries and caucuses against eventual nominee Bill Clinton, whom he tangled with on the campaign trail.
The Field Poll was conducted March 18-April 5, with 1,000 registered voters in California questioned by telephone. The survey's overall sampling error is plus or minus 3.2 percentage points.
CNN Political Editor Paul Steinhauser contributed to this report.