Elizabeth Warren, demonstrating a sustained ability to raise massive sums of money in her race against Senator Scott Brown, said Monday that she had pulled in $8.67 million between April and June, a major haul that could cement her position as the top fund-raiser among the nation's congressional candidates.
The millions Warren has raised month after month underscore how the US Senate race in Massachusetts has become a national battleground in the fight for control of the Senate and reflects the enthusiasm she has generated among wealthy donors and grass-roots activists, inside and outside Massachusetts.
Warren's fund-raising also suggests that questions about her Native American heritage have not hurt her standing with donors. Indeed, the controversy may have helped her to raise money, by energizing her liberal base.
Brown has not yet released his fund-raising figures for the most recent quarter.
Veteran political operatives said they were stunned by Warren's fund-raising prowess. She has outraised Brown in each of the three previous quarters, hauling in $15.8 million to his $8.2 million. Her biggest month to date was June, when she took in $3.1 million and received the overwhelming support of the delegates to the state's Democratic convention.
"I say to myself, 'Wow, those are huge numbers,' " said Peter J. Berlandi, who was the chief fund-raiser for Governor William F. Weld, a Republican, and for Attorney General Francis X. Bellotti, a Democrat.
While the money will allow Warren to blanket the state with ads, Berlandi said the danger for campaigns awash in cash is that they will waste money on high-priced consultants and political strategists offering services they do not need. "We still have four months to go," he said. "How much are they going to spend?"
Rob Gray, a Republican political consultant, said that "probably the closest thing we've seen to the Warren wave is the Brown wave in the final three weeks of the special election," in 2010, when Brown, then a little-known state senator, became a national sensation and quickly pulled in $15 million from Republican donors across the country.
"But his wave was limited to those three weeks," Gray said, "and she's been able to sustain it for more like eight or nine months, so it's pretty remarkable."
The Warren campaign said its fund-raising success reflected its message focused on the middle class. "It is those men and women who are fueling this campaign," Warren's campaign manager, Mindy Myers, said in a statement Monday.
Warren, a Harvard Law School professor, now has $13.5 million in the bank, according to her campaign. Brown, a Wrentham Republican, had $12.9 million in the bank in April, after raising $3.4 million in the previous quarter. Federal candidates have until Sunday to report their fundraising numbers.
Both Senate candidates are under pressure to raise millions on their own, because they have signed an agreement designed to keep outside groups from spending money on the race. Gray said that if Warren continues to raise more than Brown, some Republican-leaning groups may choose to violate that agreement and pour money into the campaign on Brown's behalf.
Polls show the race remains close. The attention it has generated has helped Warren tap liberal donors, through frequent appearances on MSNBC and a travel schedule that has taken her to California, New York, and other wellsprings of Democratic cash.
Democrats have seized on the contest as a rare chance to snatch a seat from the GOP and to propel an unflinching critic of Wall Street into the Senate.
Since she formed an exploratory committee to begin raising cash in August, Warren has hauled in $24.5 million, putting the Massachusetts Senate race on track to be one of the most expensive congressional contests in history. Rick Lazio and Hillary Rodham Clinton spent $70 million in their New York Senate race in 2000.
In 2010, Sharron Angle, the Tea Party candidate who ran unsuccessfully against Senator Harry Reid in Nevada, raised more than $13 million in one quarter, but unlike Warren's fund-raising, hers was a onetime burst.
The Warren campaign said 81 percent of its donations in the most recent quarter were for $50 or less, and 40,500 donations came from Massachusetts residents.
The campaign did not reveal how many donations came from out-of-state contributors, who have given more than half of Warren's itemized donations, sparking criticism from Republicans.
A complete list of donations of $200 or more is expected to be released by Sunday's filing deadline.
Brown, who raised more than 70 percent of his itemized contributions from out of state in the final days of the 2010 Senate race, argued that Warren's fund-raising haul shows she is beholden to forces outside Massachusetts. "Professor Warren's campaign is largely dependent on out-of-state, extreme special interests, and fellow Occupy protesters who share her radical tax, borrow and spend agenda," Alleigh Marré, a Brown campaign spokeswoman, said in a statement. "Ultimately, however, elections are decided by the voters based on competing visions for our future, and Scott Brown will have the resources he needs to share his pro-jobs message and independent record with voters across the Commonwealth."
Myers, Warren's campaign manager, said the Democrat's fund-raising would allow her to fight "Wall Street and other powerful interests."
Michael Levenson can be reached at firstname.lastname@example.org. Follow him on Twitter @mlevenson.