The haul keeps Peters on pace to have plenty of funds for his campaign against former Michigan Secretary of State Terri Lynn Land (R), who has said she'll invest millions in her campaign and posted $2 million for her first quarter in the race, including $1 million from her own pocket.

“Thanks to the overwhelming support Gary has earned from Michiganders as an independent voice for our middle class and small businesses, we are well on our way to building the strongest grassroots campaign this state has ever seen,” Peters campaign manager Julie Petrick said.

The two raised nearly identical amounts for the quarter, though Land doubled her fundraising with her own cash injection.

Land's campaign said the figures show she has the momentum.

"The third quarter shows that Terri Lynn Land beat Congressman Peters and is in position to win this Senate seat with strong support from Michigan individual donors while the federal PAC's in Washington try to prop up a floundering Peters campaign," said Land adviser John Yob.

Polling has shown a tight race to replace Sen. Carl LevinCarl LevinCongress: The sleeping watchdog Congress must not give companies tax reasons to move jobs overseas A lesson on abuse of power by Obama and his Senate allies MORE (D-Mich.), though Peters is considered the front-runner by most analysts.

—This post was updated at 10:40 a.m.