Facing one of his most difficult reelection battles in years, Rep. Barney Frank (D-Mass.) loaned his campaign $200,000 this week, according to media outlets. 

The Boston Herald reported that campaign finance documents show he raised $316,000 and had more than $1 million cash on hand. Frank's Republican opponent Sean Bielat, a former Marine, has $364,000 left to spend. 

Frank, the chairman of the House Financial Services Committee, has come under fire from Bielat for heading the committee during the 2008 financial collapse. Republicans have long made Frank a target, arguing he failed to crack down on Fannie Mae and Freddie Mac's home lending policies. 

His loan is a sign that he is taking Bielat's campaign seriously amid a Republican wave some predict could cost Democrats their majorities in Congress.

National Republicans have invested in the race and Bielat, a member of the GOP's "Young Gun" program, outraised Frank in September, $379,000 to $317,000.

The 15-term congressman, however, still has a 3-to-1 advantage over Bielat in cash on hand.