As the behind-the-scenes push for superdelegate endorsements on Capitol Hill rages on, most House Democrats from the three upcoming primary states are largely choosing to sit on the sidelines and not engage in the battle between Sens. Hillary Rodham Clinton (N.Y.) and Barack Obama (Ill.).

The highlighted exceptions are Democratic Sens. Evan Bayh (Ind.) and Bob Casey (Pa.), who have taken sides in the presidential contest — supporting Clinton and Obama, respectively. But the majority of House Members from Indiana, North Carolina and Pennsylvania are staying out of the fray until after their constituents vote later this month and in early May.

There are 23 House Democrats among the three states, yet just six have made public endorsements. Those who have made their preference known are split between the two White House hopefuls.

All three states feature rural, culturally conservative areas where House Democrats made inroads in the 2006 elections. Eight Democrats from the three states represent conservative districts won by President Bush in 2004. None of them have endorsed in the presidential contest, and they seem unlikely to do so.

Rep. Jason Altmire (Pa.), one of several Democratic freshmen who ousted a Republican incumbent in a GOP-leaning district, said he initially thought he would make an endorsement before the April 22 Pennsylvania primary but recently decided he would not.

“I’m going to wait and see what my constituents say,” Altmire said Tuesday.

Altmire also said there is “growing uneasiness” among Members about the Democratic contest dragging on until the August convention.

“We really need to bring this to a conclusion,” he said. He added that he sees evidence in his district that voters aligned with each candidate don’t like each other.

“If we don’t wrap this up, we don’t have enough time to put the pieces back together,” Altmire said.

He also noted that the Clinton campaign’s strategy of imploring superdelegates to stay on the fence is risky because it could set up a scenario where a large group of Members come out and issue an endorsement at the same time — presumably backing Obama, who is leading Clinton in pledged delegates.

Rep. Tim Holden (D-Pa.) said he has told both campaigns that he will not make an endorsement before the primary.

“I have a district that’s divided about this,” Holden said, adding that it’s his preference to let the voters make their choice before he does. Still, he acknowledged that Members likely won’t be able to sit on the fence forever.

“At some point, you’re going to have to make a decision,” he said.

The Obama campaign is trying to flush Members out — especially those in conservative districts — to make public endorsements. One of the Obama campaign’s talking points in making their case to Members has been that the Illinois Senator would be better at the top of the ticket than a polarizing figure such as Clinton.

Democratic pollster Alan Secrest, who regularly works for candidates running in more GOP-friendly territory, said that by November any such advantage will likely prove elusive.

“Certainly the Obama campaign is trying to make the argument that he will be a better ticket mate in the fall than she will,” he said. “I think most people discount that argument. It has some appeal at the moment. … I think most close observers believe come fall most of that advantage will be erased.”

Secrest said the Members he has spoken with are largely taking a wait-and-see approach and are confident that the nomination process will work and produce a nominee before the convention.

“I think a lot of Members are really taking their role fairly seriously here,” he said. “Some of those who I’ve spoken with … really believe the best approach is to wait and to give the process further opportunity to resolve itself before they weigh in or before they endorse.”

Primary voters in Indiana and North Carolina will go to the polls on May 6. Only one House Democrat from the two delegations has made an endorsement — Rep. G.K. Butterfield (D-N.C.) is backing Obama.

Butterfield is lobbying his colleagues on behalf of Obama. An earlier news report that the Democrats in the delegation were planning to endorse Obama as a group was erroneous and Butterfield said it is very doubtful that scenario will eventually happen.

“We’re working very hard to earn their endorsement,” he said. “We’re not going to give up.”

Rep. Brad Miller (D-N.C.) said he won’t make any endorsement before the Pennsylvania primary and remains undecided about whether he will endorse before May 6.

“I don’t think I would move many votes on my own staff or my own family,” he said.

Miller said while his nieces and nephews are supporting Obama, his 93-year-old mother asked his brother to get a Clinton yard sign for her.

Meanwhile, none of the five Democratic Congressmen from Indiana has endorsed a candidate.

“I haven’t seen any movement at all within the delegation, at all,” said Micah Ragland, press secretary for Rep. André Carson (D-Ind.). “Most are staying out of it. Nobody wants to make that risky move.”

The highest-profile endorsement in the state is from former Indiana Congressman and 9/11 commission Chairman Lee Hamilton, who last month pledged support for Obama.

He said he was prompted to make his announcement in time for the primary but also because Indiana residents kept approaching him after talks he gave around the state and asking him which candidate he supported.

Hamilton said he talks with the state’s Congressional Democrats sporadically and said that Rep. Baron Hill (D-Ind.) called him after his announcement to ask about it.

Miller said he believed the nomination will be decided before August and that pressure to resolve the contest will mount after the Pennsylvania, Indiana and North Carolina primaries.

“There will be a strong effort to get the undeclared delegates to decide and announce their decision early,” Miller said, “so that we can have a nominee and can begin the fall campaign.”

Rep. David Price (D-N.C.) acknowledged that the lobbying for endorsements hasn’t reached it’s peak.

“There’s lots of communication but nothing I would describe as pressure,” Price said.

Jennifer Bendery contributed to this report.