Newark Mayor Cory Booker dominated his New Jersey Senate special-election foes in fundraising during the first three weeks of July, pre-primary reports filed with the Federal Election Commission showed.

Booker raised $2.1 million from July 1 to 24 — six times more than his closest competitor in the Aug. 13 race for the Democratic nomination.

Booker reported having more than $4 million in cash on hand by the end of the pre-primary period. Reports were due to the FEC on Aug. 1.

The mayor is heavily favored to advance to the Oct. 16 special election and win the seat of the late Sen. Frank R. Lautenberg. The last three weeks of fundraising were a continuation of what’s transpired in the race so far.

At the start of the campaign, Booker’s greatest challenge appeared to be in the Democratic primary, but public polling has shown him with wide leads. The Quinnipiac University Polling Institute is set to release another poll on the race Wednesday.

As for the competition, Rep. Rush D. Holt raised $356,000 over the three weeks, Rep. Frank Pallone Jr. raised $180,000 and state Speaker Sheila Oliver raised $12,000. Among the three, Pallone led in cash on hand with $2.6 million, followed by Holt with $667,000 and Oliver with less than $5,000.

Steve Lonegan, the likely Republican nominee, raised $130,000 in the pre-primary period and had $151,000 in cash on hand. He made the rounds last week in Washington, D.C., hoping to drum up financial support.

The race is rated Safe Democrat by Rothenberg Political Report/Roll Call. There will be another election for this seat in 2014, that time for a full six-year term.