Less than 24 hours after being welcomed into the Democratic fold as a hero, Sen. Arlen Specter (Pa.) found himself chastised by his new leadership, demoted to freshman status and forced to use the chamber’s back door to avoid reporters’ questions about his loyalties.

“He’s kind of a man without a country right now,— Sen. Claire McCaskill (D-Mo.) said of her newest colleague, who on Tuesday watched as Majority Leader Harry Reid (D-Nev.) was forced to renege on the deal they cut when Specter switched parties.

Reid had publicly said Specter would keep his seniority on five committees, although he would not be given the chairmanship of any committees or subcommittees.

But Specter’s 28 years in the Senate would have put him ahead of much of the Democratic Conference, and backlash from senior Democrats, including Sens. Tom Harkin (Iowa) and Dianne Feinstein (Calif.), forced Reid on Tuesday to officially strip the Pennsylvanian of his seniority.

Reid’s office said the issue will be revisited in 2011 when the 112th Congress begins, assuming Specter is re-elected next year.

McCaskill and other Democrats acknowledged the intraparty turf war had forced Reid’s hand.

“It’s hard for people who’ve been here for a while,— McCaskill said, explaining that “seniority is obviously a very sticky wicket. It’s hard for folks that have been here for a while that he would walk over from the other side and suddenly be at the top— of the seniority list.

In a statement put out by his office Tuesday, Specter acknowledged his colleagues’ concerns and said he was willing to put off a final decision on his seniority until the beginning of the next Congress.

“Some members of the caucus have raised concerns about my seniority, so the caucus will vote on my seniority at the same time subcommittee chairmanships are confirmed after the 2010 election. I am confident my seniority will be maintained under the arrangement I worked out with Senator Reid,— Specter said in the statement.

Democrats were largely forgiving of Specter for trying to keep his seniority. “I don’t think he’s overstepped his bounds. I think he misspoke about seniority. It’s a matter of what you ask for and what you get,— Sen. Ben Nelson (D-Neb.) said.

Sen. Frank Lautenberg (D-N.J.) — who had his 18 years of seniority stripped when he returned to the Senate in 2002 despite an agreement with Democratic leaders that it would be reinstated — said it is a difficult process to go through. “I know that I was disappointed when I went back 35 places— in the Democratic pecking order, Lautenberg said.

Privately, however, some Democrats complained that Reid didn’t vet his initial decision on Specter’s seniority with members of his Conference.

Specter and Reid, in the hours and days following Specter’s party switch, repeatedly said that while the new Democrat would not be given a gavel during this session, he would be treated as if he had served his entire Senate career as a Democrat.

During an April 28 press conference, Reid responded to a question regarding Specter’s status on committees by saying that, while no gavels would change hands, he would keep his seniority.

“Sen. Specter knows that no one will be dumped off of a full committee or a subcommittee, unless it’s done on some voluntary basis. Of course in a year and a half, as we start every Congress, it’s a new game. And Sen. Specter has seniority, over a number of people, in the committees that he wants to serve on,— Reid said.

That, in turn fed the Capitol’s rumor mill, which had Specter replacing a senior Democrat such as Harkin, who chairs the Appropriations Subcommittee on Labor, Health and Human Services, and Education.

The combination of that speculation and Reid’s public statements ultimately led to the strong pushback from veteran members of the Conference, Democrats said.

Reid spokesman Jim Manley said the confusion surrounding Specter’s seniority was a result of the speed with which his switch took place.

“This all happened very quickly. As best as I can tell, word leaked out prematurely,— sending some Members scrambling to protect their turf, Manley explained. “Everyone should just calm down a bit. As always, these things will work themselves out.—

Complicating matters, the formal decision to demote him came as fresh questions about Specter’s ability to fit in with his new colleagues swirled around the Capitol.

Democrats said that his vote against the Democratic budget, his opposition to a labor reform bill, his insistence that he will not be “a loyal Democrat— at all times and comments he made to the New York Times Magazine backing former Sen. Norm Coleman’s (R-Minn.) re-election bid all caused frustration.

Specter, normally a favorite of reporters, found himself besieged much of the day Tuesday and largely avoided the press.

During an interview on MSNBC on Tuesday, Reid said that while Specter’s comments in recent days have caused heartburn in his caucus, he is willing to accept Specter’s explanation that the Coleman comment was an unintentional slip. “He created a few questions with my caucus. I went to him last night and he said it wasn’t really what he meant, so I accept that,— Reid said.

Reid also said he expects that Specter will support Democrats on procedural votes despite Specter’s insistence that he will not vote in lock step with his new party. “I think Arlen will be a good vote. He’s a moderate person, and he fits in very well with the caucus. On procedural votes he will be with us. There’s a lot for him to get used to and a lot for us to get used to,— Reid said.

White House Press Secretary Robert Gibbs said that despite Specter’s indiscretions, he continues to enjoy President Barack Obama’s support, and Obama will do what he must to get him re-elected.

“I think Sen. Specter said it the day he made his announcement that he’s going to make decisions on individual bills,— Gibbs said. “We don’t generally get a hundred percent of any party voting for us, but we’ll continue to try.—

Likewise, McCaskill predicted that in the end Democrats would come to accept their new member. “The road will be rocky for a little while as people get used to him,— she said.

Jessica Brady and Keith Koffler contributed to this report.