By Christopher Baxter and Jarrett Renshaw/The Star-Ledger

TRENTON — Gov. Chris Christie today called for a special election in October to fill the U.S. Senate seat left vacant by the death of Frank Lautenberg, spurring an all-out sprint for the office and drawing fire from Democrats.

Within minutes of the announcement, potential candidates — including U.S. Reps. Frank Pallone and Rush Holt, both Democrats, and state Sen. Michael Doherty and Assemblyman Jon Bramnick, both Republicans — signaled they were mulling a run.

"The gun has been fired," Christie said at a Statehouse news conference "It’s time to go. You’re in, you’re in. Get going. Get running."

The governor 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.

Those who want to run in the primary must file petitions with at least 1,000 signatures by 4 p.m. Monday.

Christie’s decision means New Jersey will hold two general elections within several weeks this year. The Nov. 5 ballot features the governor’s race and contests for all 120 seats of state Legislature.

Pallone (D-6th Dist.) intends to run for the seat, three sources with knowledge of the congressman’s thinking told The Star-Ledger. One of the sources, who requested anonymity out of respect for Lautenberg, said Pallone had called Democrats to inform them of his plans.

Representatives of Pallone and Holt (D-12th Dist.) said no announcements would be made until after Lautenberg’s funeral.

In Newark, Booker’s spokesman, Kevin Griffis, said, "For several months now, the mayor has been taking the steps necessary to run, but he will make an official announcement at the appropriate time."

Bramnick (R-Union) did not confirm a run but added, "I haven’t ruled that out, that’s for sure."

Doherty (R-Warren), one of the state’s most conservative lawmakers, said his decision rested on who else might run.

"You don’t step on a battlefield unless you think you can win," he said.

Star-Ledger staff writers David Giambusso and Matt Friedman contributed to this report.

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