Facing a firestorm of controversy over the release of damaging allegations back home, Illinois Senate nominee Jack Ryan (R) will travel to Washington, D.C., today to raise money and support for a campaign in peril.

National Republican Senatorial Committee Chairman George Allen (Va.) will be the special guest at a fundraising event, scheduled from noon to 1:30 p.m., at Charlie Palmer Steak on Capitol Hill.

About 10 to 15 high-level political action committee representatives are expected to attend the luncheon, which had been scheduled long before the allegations surfaced this week that Ryan forced his then-wife to go to “explicit sex clubs” in New York, New Orleans and Paris.

The NRSC chairman and other Senate Republicans are standing by Ryan for now, amid calls from others in the party for him to exit the race.

Allen regularly holds small gatherings like the one featuring Ryan as a way to introduce candidates to the PAC community and donors on K Street.

Another D.C. fundraiser that Ryan had scheduled for this morning was postponed after Speaker Dennis Hastert (R-Ill.), a headliner of the event, was called to a meeting at the White House.

While Ryan aides have denied that the controversy has had a negative impact on fundraising so far, there are already indications from K Street that the fallout from the public release of Ryan’s child custody battle proceedings is only just beginning.

Ryan is vowing to stay in the race and repair his damaged image, but some question whether he can survive as the party’s nominee.

“I think he’s walking dead after this latest story,” said one GOP lobbyist, who is not attending today’s luncheon.

“The nature of this story is a little bit of a killer. I think probably an even a bigger killer is that I don’t think he played fair with people.”

While Senate Republicans have indicated their support for Ryan, Hastert said Wednesday that he is reserving judgment and comment until he can speak directly with Ryan.

As the allegations about the Senate nominee continued to dominate the Illinois media Wednesday, much of the state’s House delegation remained silent about Ryan and the future viability of his campaign.

Even before this week’s storm of controversy, Ryan was already facing an uphill battle in the race to succeed retiring Sen. Peter Fitzgerald (R) in November.

Polls have shown Ryan trailing state Sen. Barack Obama (D) by as much as 22 points in the past month, as Ryan’s campaign has endured at least one highly publicized stumble in recent weeks.

Obama, who happened to be in Washington for a fundraiser with Sen. Hillary Rodham Clinton (D-N.Y.) on Wednesday, has declined to comment on the Ryan situation and has said he is focusing his campaign on the issues.

The state lawmaker, who gained instant stardom in the party after winning the March primary, has been tapped to give the weekly Democratic radio address this weekend.