The Democratic Senatorial Campaign Committee (DSCC) raised $15.5 million during September, more than double what it took in during the month of August.
Meanwhile, the National Republican Senatorial Committee pulled in about half the money its Democratic counterpart raised. The NRCC took in $8.3 million last month while spending $13.6 million. It now has $19.2 million banked for the final stretch of the campaign. The DSCC has $25.6 million cash on hand for the final few weeks of campaigning.
Republicans sought to downplay their financial disadvantage.
"While we've always expected to be outraised and outspent by the Democrats, the reality is that they've now been forced to abandon a number of their candidates on the campaign battlefield, including Robin Carnahan in Missouri just this week, and have assumed an almost purely defensive posture," Rob Jesmer, the NRSC's executive director, said in a statement. "Senate Republicans are not only on offense in at least ten Democrat-held Senate seats, but we’re shifting even greater financial resources into blue states like California, Washington, and Illinois."
Close to $2 million of the DSCC's September haul came in the form of a transfer from the Democratic National Committee. Sen. Charles Schumer (D-N.Y.) gave another $1 million.
Still, the DSCC's haul is a sizable one. In all, the committee took in more than $27 million in the third quarter of the year.
"Democrats are increasingly unified and motivated in the final stretch of the midterm elections," DSCC Executive Director J.B. Poersch said in a statement. "As Republicans nominate extremists who want to return to the failed Bush economic policies of the past, Democrats are ready to fight."
In August, the DSCC topped the NRSC by more than $1 million, raising $7.4 million to the NRSC's $6 million.
--Updated at 4:10 p.m.
--Sean J. Miller contributed to this post.