The Democratic Congressional Campaign Committee outraised its Republican counterpart in March by about $400,000.
President Obama continued lending support to the DCCC last month, appearing at a Miami fundraiser.
The DCCC raised more money from January through March, hauling in $23.6 million to the NRCC's $21.2 million. Neither committee is carrying any debt.
House Democrats need to pick up 17 seats to win back the majority, a goal that strategists in both parties agree is all but impossible.