Sen. Hillary Rodham Clinton’s supporters in the Rhode Island congressional delegation said today that they still back her presidential candidacy. But Sen. Sheldon Whitehouse and Rep. James R. Langevin both indicated that they might reassess their endorsements if Clinton stays in the race much beyond rival Sen. Barack Obama’s expected claim to a nominating majority.

"I want to be with her, whatever she decides,’’ said Langevin, who noted that Clinton handily defeated Obama in Rhode Island’s Democratic presidential primary. He spoke as voters in South Dakota and Montana cast the last Democratic primary votes.

Langevin said he believes the nomination "will resolve itself at some point. I believe it could be as early as this week.’’ But "if the issue has not been resolved’’ by early next week, Langevin said, "we will all start to reflect and reassess.’’

Whitehouse reiterated that he thinks Clinton would be the better candidate in November and phrased his commentary to leave open the possibility that she might yet become the nominee. Whitehouse also suggested that the Democratic contest could continue another month without hurting the party.

"There may come a time when I think for the benefit of the party’’ that either Clinton or Obama "has to give way,’’ Whitehouse said.

If "it gets to be the Fourth of July’’ and the campaign is still going, "that’s my internal gyroscope as to where it probably starts to turn adverse for the party,’’ Whitehouse said. At that point, Whitehouse said he might consider calling for Clinton to withdraw, but he stressed that he doesn’t want to rule out the possibility that she could still be the nominee.

In separate telephone interviews, Whitehouse and Langevin were circumspect in their comments about Clinton, praising her candidacy, reiterating their support for her, and deferring to her judgment on whether and how to leave the field.

Both avoided a direct answer to the question of whether they would support Clinton if she judges that she should fight all the way to the floor of the Democratic convention in Denver this summer.

Meanwhile, Rhode Island’s most prominent uncommitted superdelegate, Sen. Jack Reed, said he isn’t ready yet to endorse a candidate.

Reed said he doesn’t plan to join any organized swing of undeclared superdelegates into Obama’s camp tomorrow. Reed did say it’s important for the party to unify soon behind a candidate for the fall election. As the same time, however, Reed said the hard-fought Democratic campaign has been good for the party in a number of ways, and he said the candidates should be allowed some room to make the transition to unity behind one standard-bearer.

Rep. Patrick J. Kennedy, an Obama supporter, was unavailable for an interview because he was in North Carolina as his father, Sen. Edward M. Kennedy, underwent surgery yesterday for his malignant brain tumor.

The four Rhode Islanders, like all Democratic members of Congress, are among the superdelegates who are automatically granted votes at the presidential nominating convention. Unlike ordinary delegates, they do not have to run in a primary election as supporters of a presidential candidate.

In the aggregate, the superdelegates have an outsized influence this year because of the close division of regular delegates on support for Clinton or Obama.