Illinois Republicans took two steps out of campaign limbo Thursday as their scandal-tainted Senate nominee officially withdrew his candidacy and party leaders set a date to pick his replacement.

Jack Ryan (search), whose continued presence on the ballot had frustrated Republican leaders, finally filed his withdrawal papers with the Illinois State Board of Elections Thursday morning.

"What a relief!" Ronald Smith, secretary of the Republican State Central Committee, said when told Ryan had officially dropped out.

The Republican Party will pick a replacement candidate Tuesday, chairwoman Judy Baar Topinka said later Thursday.

Ryan, a millionaire investment banker-turned-teacher, said he would exit the race last month after embarrassing sex allegations by his ex-wife, "Star Trek: Voyager" and "Boston Public" actress Jeri Ryan, became public. In custody papers, she accused him of dragging her to sex clubs and asking her to have sex with him in front of others.

His spokesman, Bill Pascoe, said Ryan has been traveling and spending time with his family, and filling out the necessary paperwork to get off the ballot was not a priority.

"This is perfunctory. Jack made very clear five weeks ago that he was going to withdraw from the race," Pascoe said.

The lack of a candidate to replace retiring GOP Sen. Peter Fitzgerald has been a lingering embarrassment to Illinois Republicans, who are still trying to recover from the indictment of former Gov. George Ryan in a widespread corruption scandal and a disastrous 2002 election in which it lost almost every statewide office. But Republican leaders say that with just over three months before the Nov. 2 election, there is still time to challenge the Democratic nominee, state Sen. Barack Obama.

Topinka said six to 12 potential candidates will give presentations and be questioned by committee members during a meeting Tuesday in Chicago before the central committee.

Topinka refused to say who is on the list of potential candidates or who has been interviewed by party leaders.

Many party stalwarts and well-known GOP figures already have turned down the chance to run against Obama, who led Ryan in polls before the scandal broke and has only gained in fund-raising and name recognition while the Republicans have been in disarray.

Obama delivered the keynote address at the Democratic National Convention on Tuesday to rave reviews and is viewed as a rising star in the party.

But Topinka said that Republicans will put financial resources into the race and can still win it. Obama "did a great job the other night at the convention, but we're not talking issues," Topinka said. "It can't just be a free ride."

Among the people who have declined to run are former Govs. Jim Edgar and James Thompson and former Chicago Bears head coach Mike Ditka.