Massachusetts Senate candidate Elizabeth Warren raised $6.9 million in the first quarter of 2012. This figure represents slightly more than twice the amount raised by incumbent Sen. Scott Brown, whose campaign announced last week that it had raised $3.4 million.

Warren has out-raised Brown for the past three quarters. She raised $3.15 million to Brown's $1.55 million in the third quarter of last year, and $5.7 million to Brown's $3.2 million in the fourth quarter.

Despite the strength of her fundraising, however, Brown has more money in the bank. The Brown campaign has around $15 million cash on hand, which includes money left over from his 2010 campaign.

Warren, the Harvard Law professor and presumptive Democratic nominee, has about $4 million less, according to an email sent to supporters from her campaign manager.

A Boston Globe poll out last week showed Warren and Brown in a virtual dead heat. Thirty-seven percent of those polled said they supported Brown, while 35 percent said that they supported Warren.

The poll had a margin of error of plus-minus 4.2 percent.