Elizabeth Warren, left, holds up a poster of herself as Sen. Scott Brown (R-Mass.) right, looks on during the annual St. Patrick's Day Breakfast in Boston, Sunday, March 18, 2012. Warren, a Harvard professor and consumer advocate, is running against Brown who once posed for a centerfold in Cosmopolitan magazine. (AP Photo/Michael Dwyer)

Even though Warren has been in the campaign for less than seven months, she has already raised $15.8 million and has about $11 million cash on hand.

That’s still less than Brown, who raised $3.4 million in the first quarter and had $15 million in the bank as of March 31, but given how quickly Warren is raising money, she should close that gap by Election Day.

“The incredible enthusiasm we have seen from people across the Commonwealth who are contributing to this campaign shows the strong grassroots momentum behind Elizabeth’s fight for middle class families,” said Warren campaign manager Mindy Myers. “Scott Brown still has $4 million more in the bank than we do, but this is the kind of support we need to be able to take on the big banks and corporations that are lining up against Elizabeth.”

The two candidates have agreed to a pact that discourages outside groups from taking part in their campaign, but their race still promises to be the most expensive Senate race of the year and possibly the most expensive ever.

That title belongs to the the Hillary Clinton/Rick Lazio campaign in New York in 2000, when the two combined to raise and spent $70 million.

With seven months to go in the 2012 campaign, Brown and Warren have already combined for $35 million — a strong indication that they may eclipse that race.

Warren’s total isn’t a record for a Senate candidate — Lazio raised about $22 million in the third quarter of 2000 as his race with Clinton ramped up and Nevada GOP Senate candidate Sharron Angle raised $14 million in the third quarter of 2010 — but it certainly ranks up there with the biggest fundraising quarters of all time, and it happened during a relatively sleepy portion of the campaign.

Warren came up just shy of setting the record for the first quarter of an election year, according to data from the Campaign Finance Institute. In that same New York Senate race that Lazio and Clinton set the record, former New York mayor Rudy Giuliani (R) raised $7.4 million in the first quarter before dropping out of the race.