Sean Bielat’s campaign raised more money over the last month than the Massachusetts Republican Congressional candidate had received in the first 20 months of this cycle combined.

It doesn’t hurt that Bielat’s opponent is Rep. Barney Frank (D-Mass.), the Financial Services chairman who is the poster child for the nation’s financial woes among conservatives.

Fueled by a host of recent media appearances on Fox News and other national outlets, Bielat disclosed Friday that he raised roughly $400,000 since Aug. 25 and had that same amount, $400,000, on hand at the end of September.

Through Aug. 25, Bielat, a Marine and local businessman, had taken in less than $232,000 for the entire cycle and reported only $84,000 in cash on hand.

“It’s unbelievable. The trajectory is going in the right direction,” said Bielat spokeswoman Lisa Barstow. “Sean has said from the start that we don’t need to be toe to toe with Barney on fundraising. But we need enough to be competitive. And we’re on track to exceed our expectations.”

Frank, meanwhile, reported more than $1 million on hand at the end of August. And that was before President Bill Clinton visited the southeastern Massachusetts district to stump for him, an event that was not a fundraiser and actually cost the campaign money.

There’s little doubt that the GOP is trying to build momentum for this political novice, who many believe has little chance of knocking off a powerful incumbent in an overwhelmingly blue district. (President Barack Obama won the district by 29 points in 2008.)

The National Republican Congressional Committee this week elevated Bielat to “On the Radar” status as part of its Young Guns program. The promotion was released the same day that former Massachusetts Gov. Mitt Romney endorsed Bielat.

And less than two weeks ago, the Bielat campaign released an internal poll that showed Bielat trailing the 15-term Congressman by just 10 points.

The fundraising boost should ensure that Bielat can purchase at least some television time in the expensive Boston or Providence markets in the final week or two of the campaign. Barlow said decisions about a specific media strategy will be made next week.