John McCain has begun to raise eyebrows in Republican circles for his lack of fundraising help on behalf of his party’s House and Senate campaign committees.

The Arizona senator has yet to send a fundraising appeal for those committees nearly four months after becoming his party’s presumptive nominee, and he skipped out on a major fundraising dinner for them in recent weeks.

The e-mail was in response to the $21.5 million the GOP raised two weeks ago at the President’s Dinner, a big fundraiser for the National Republican Congressional Committee (NRCC) and National Republican Senatorial Committee (NRSC). McCain skipped the dinner, even though the party’s presidential nominee usually attends.

NRSC spokeswoman Rebecca Fisher said there are no commitments yet between McCain and the committee, but that Obama’s fundraising e-mails put things into perspective.

“Trust me, we all noticed,” Fisher said of the e-mails. “A, that would be huge for them. Just seeing that he did an e-mail for [the Democratic Senatorial Campaign Committee], we said, ‘That’s going to be a significant e-mail.’ And B, we noticed there hasn’t been one on our end. We look forward to when John McCain does one for us.”

An NRCC source said McCain has agreed to help the committee in some capacity but the details were being worked out. His help could come in the form of an e-mail, a mailer or an appearance at an event and is likely to be similar to his effort for the NRSC.

McCain’s campaign did not comment by press time.

Obama’s ability to attract new and small donors is a valuable commodity for Democrats, and he has done a number of appeals for the House and Senate committees over the years.

His campaign has also made a point of involving down-ballot candidates in his presidential campaign and stressed their importance in a strategy briefing with reporters last week. So far this year, he has taken time out to cut ads for Reps. Bill Foster (D-Ill.) and John Barrow (D-Ga.).

McCain hasn’t proven nearly as prolific a fundraiser as Obama has, and questions remain about the GOP candidate’s appeal to the base of the party, which has in large part balked at helping the NRCC and NRSC for much of the cycle.

Many blame one of McCain’s signature issues, comprehensive immigration reform, for that dry spell.

His absence at the President’s Dinner was largely seen as a nod to the difficulties he has separating himself in the general election from an unpopular President Bush.

At the end of May, the Democratic House and Senate committees had about three times as much cash on hand as Republicans, $85.7 million to $28.3 million. Those numbers, though, don’t include the President’s Dinner money.

The NRCC, in particular, has struggled with leftover debt from last cycle and an ongoing investigation into alleged fraud by its former treasurer.

“We’re just excited that he’s going to be helping our efforts to elect House Republicans,” NRCC spokeswoman Julie Shutley said. “That’s the main point. He is the best nominee that Republicans could have chosen for us this cycle.”