New Jersey Democrat Cory Booker has raised $4.6 million in the past three months as he seeks a U.S. Senate seat in a special election.
Booker's campaign was the first to announce a second-quarter fundraising total today.
Candidates have until Monday to file with federal election officials.
The Newark mayor faces three others seeking the Democratic nomination for the seat -- U.S. Representative Frank Pallone, state Representative Rush Holt and state Assembly Speaker Sheila Oliver.
On the Republican side, former Bogota Mayor Steve Lonegan and Alietta Eck, a doctor from Piscataway, are on the ballot in the Aug. 13 primaries.
The general election is Oct. 16 to fill the last year of Sen. Frank Lautenberg's term.
The nation's oldest senator died in office last month. He was 89.
Last week, the Lautenberg family attacked Booker and endorsed Pallone.
The late senator's son, Josh Lautenberg, told the Associated Press that Booker is more concerned with being a celebrity than serving the people of New Jersey.
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