NEWARK — Mayor Cory Booker will run in a special primary for U.S. Senate, according to two people briefed on his plans.

The advisers, who requested anonymity in advance of an official announcement, said the mayor will declare his intentions to run in an August primary to fill the seat of U.S. Sen. Frank Lautenberg, who died Monday. Booker will have two events Saturday, one in Newark and one in South Jersey.

UPDATE:

Booker will officially launch U.S. Senate run on Saturday with events in Newark, Willingboro

His announcement could be affected by inclement weather expected from Tropical Storm Andrea, but the campaign will provide more details later today.

The campaign has already begun beefing up its staff, including the hiring of Message and Media, a top political consulting firm.

On Tuesday, Gov. Chris Christie set the Democratic and Republican special primaries for Aug. 13, and the special general election for Oct. 16. The winner of the general election will serve the remainder of Lautenberg's term, and the next election will be held, on schedule, in November 2014.

On Wednesday night, Booker spokesman Kevin Griffis confirmed that the mayor was collecting the 1,000 signatures needed to run in the August primary.

Those who want to run in the primary must file petitions by 4 p.m. Monday.

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