UPDATED: Obama endorses Booker

Newark Mayor and U.S. Senate candidate Cory Booker addresses a gathering after winning the Democratic primary election for the seat vacated by the late U.S. Sen. Frank Lautenberg, Tuesday, Aug. 13, 2013, in Newark, N.J. Lautenberg died in June. Booker and Republican Steve Lonegan will square off in an Oct. 16 special election, with the winner headed to Washington to serve the remaining 15 months of Lautenberg's term. (AP Photo/Mel Evans)

UPDATED with comments from Steve Lonegan

WASHINGTON -- President Obama formally endorsed Newark Mayor Cory Booker in the New Jersey Senate race Wednesday, one day after Gov. Christie backed Republican nominee Steve Lonegan.

"Cory has time and again taken on tough challenges, fought for the middle class and those working to join it, and forged coalitions that create progress - and that's the spirit he'll carry with him to Washington," Obama said in a statement released by the Booker campaign. "His passion for his city has helped create new jobs and attract some of America’s top businesses to Newark. Cory will be an important partner in our efforts to reduce gun violence, give every American a fair shot in a global economy, and make our country stronger."

Booker said he was "humbled" by the endorsement.

"The President has taken on the difficult fights. He worked to turn around our economy, to make high-quality, affordable health care available to every American and to keep our country safe," Booker said. "I look forward to continuing to work with him to advance an agenda that spreads prosperity and ensures that our nation realizes the promise of its founding."

The president's endorsement was expected. Obviously he wants to keep the Senate in Democratic hands, and Booker's campaign team is filled with former Obama campaign staffers. Politico recently reported on their friendly personal relationship.

How much will Obama's backing help?

A Monmouth University/Asbury Park Press poll out Tuesday found that likely voters in the Oct. 16 race approve of Obama's job performance, but by a relatively narrow marging of 49-43, considering New Jersey's typical political leanings.

UPDATED: Lonegan called Booker a "strong and enthusiastic rubber stamp for the Obama agenda" with "radical ideas even further to the left" of the president.

"People in New Jersey are sick of Barack Obama’s lies, his health care plan, his data collection and his inability to lead our nation back to economic prosperity," Lonegan said in a statement. "Cory Booker is too liberal for New Jersey."

Lonegan was set to receive an endorsement from New Jersey's Republican Sen. Jeff Chiesa this afternoon. Chiesa is a close Christie ally appointed to temporarily fill-in after the death of the late Sen. Frank Lautenberg, a Democrat. He will serve until after the Oct. 16 general election.

The Monmouth poll gave Booker a 16-point lead over Lonegan as the general election campaign begins.

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