March 27 (Bloomberg) -- The prospect of a Hillary Clinton victory in Pennsylvania's April 22 Democratic primary isn't swaying some of the state's superdelegates, who are hanging back while they calculate whether rival Barack Obama might prove a stronger draw at the top of the ticket in November.

While the New York senator is leading in polls, some undecided superdelegates -- elected officials who get an automatic vote on the party presidential nomination regardless of the primary's outcome -- say they are concerned that her nomination would motivate greater numbers of Republicans to turn out in November to vote against her, and other Democrats too.

``If we nominate Senator Clinton, it is possible we are going to stir up the passions of people on the far right who otherwise would not be very excited about this election,'' said Representative Jason Altmire, a freshman Democrat in a competitive re-election race. ``And I do have that concern.''

The issue is critical for Clinton, whose hopes of winning the nomination depend on sweeping up most of the superdelegates nationwide to offset her deficit among delegates picked in primaries and caucuses.

Altmire, 40, whose Pittsburgh suburban district gave President George W. Bush 54 percent of its vote in 2004, said he is struggling to determine whether either candidate would provide ``coattails'' in his race.

`High Negatives'

He said he is concerned that Clinton's ``high negatives'' might increase the turnout for the presumptive Republican choice, John McCain, also benefiting that party's House candidates.

Representative Chris Carney, also a superdelegate and first-term Democrat, said he would make an endorsement after the primary if a candidate wins by a ``landslide'' in his northeast Pennsylvania district, which favored Bush with 60 percent of the vote in 2004. ``I'm going to wait and see how my district votes,'' he said.

Carney, 49, said he didn't know whether Obama or Clinton would be better for his re-election bid. Clinton's negatives are ``widely known,'' he said. ``What we don't know is whether the other shoe is going to drop for Mr. Obama.''

Another Democrat in a Republican district, eighth-term Representative Tim Holden, has told Pennsylvania newspapers he doesn't intend to endorse anyone now that the candidate he liked most, New Mexico Governor Bill Richardson, has dropped out.

Leading Obama

Altmire said ``it remains to be seen'' how Clinton would do in his district, though he expects her to ``do pretty well'' in the state. A March 10-16 survey by Quinnipiac University showed her leading Obama in Pennsylvania, 53 percent to 41 percent.

Even if Clinton, 60, wins the state, she will net just a handful of pledged delegates. Her recent victory in Ohio, where she beat Obama 54 percent to 44 percent, netted her only nine more delegates than her rival.

Obama, 46, leads Clinton 1,406 to 1,249 in the number of pledged delegates -- those awarded through the primaries and caucuses -- according to an unofficial tally by the Associated Press; 2,024 delegate votes are needed to win the nomination.

Both sides acknowledge Clinton's chances for the nomination rest with the 794 superdelegates nationwide. While Obama has picked up more than Clinton in recent weeks, she still has a slim advantage, with 250 to his 215.

Unharmed

Obama and Clinton are tied, each with 45 percent support among Democratic voters, suggesting the Illinois senator has been neither helped nor harmed by a controversy over his former church minister, the Wall Street Journal reported today, citing a Wall Street Journal/NBC News poll. The last such poll, two weeks ago, had Clinton leading, 47 percent to 43 percent.

The survey of 700 voters was taken March 24-25 and had a margin of error of 3.7 percentage points. In a March 18 address on race, Obama criticized the Reverend Jeremiah Wright Jr. for condemning the U.S. for racial injustices, but refused to renounce him.

In Pennsylvania, Clinton won early support from Governor Ed Rendell and Philadelphia Mayor Michael Nutter, and Representative John Murtha, a leading opponent of the Iraq War, joined her side last week. So far, she has the endorsements of 14 of the state's 29 superdelegates; Obama has five.

Pennsylvania has four of 30 House seats that Democrats picked up from Republicans in 2006, more than any other state. Republicans are targeting several of those freshmen this year.

Quick to Endorse

Two of those freshmen were quick to endorse. Representative Joe Sestak, a retired three-star admiral, endorsed Clinton. Representative Patrick Murphy, an Iraq War veteran, sided with Obama. Both are from suburban Philadelphia districts that have leaned Democratic in presidential races.

The considerations of the Pennsylvania lawmakers who haven't announced their preference are similar to those of the 40 percent of superdelegates who remain unpledged, said Bruce Larson, chairman of the political science department at Gettysburg College. These Democrats in Republican districts want to ``raise as little controversy as possible,'' he said.

Carney won his seat in one of the upsets of 2006, after the Republican incumbent, Don Sherwood, became embroiled in a sex scandal. His 2008 race is rated competitive by the Cook Political Report, a nonpartisan group in Washington.

Carney said Clinton appealed for his vote in a March 19 telephone call; Obama has called him three times since last summer. Obama has also recruited Carney's mother to help his campaign in Iowa, where she lives; she too is lobbying the congressman to back Obama. ``She said, `Chris, this is your mother talking to you now,''' Carney said.

To contact the reporter on this story: Laura Litvan in Washington at llitvan@bloomberg.net

Last Updated: March 27, 2008 05:31 EDT