WASHINGTON — Rep. Jason Altmire, a freshman Democrat from Pennsylvania, is in a pickle. He wants to stay in sync with his constituents, who he expects will vote for New York Sen. Hillary Rodham Clinton in his state's April 22 Democratic presidential primary. But he fears her nomination could mobilize conservative Republicans who loathe her -- which might make his own reelection more difficult in the fall.
No wonder he is undecided about whether to endorse her or her party rival, Sen. Barack Obama of Illinois.
Altmire is part of a unique and influential constituency in the stretch drive of the Democratic presidential race: members of Congress -- who make up more than a third of superdelegates-- who are poised to decide whether Clinton or Obama will be the party's nominee.
This group is a particularly sensitive bellwether as Democrats weigh their options because, unlike the average voter, lawmakers up for reelection also have their own political self-interest at stake in who ascends to the top of the ticket. The party's nominee can provide either coattails or head winds for lawmakers such as Altmire, who won his seat in an upset with only 52% of the vote.
"The key decision for superdelegates, especially elected officials, is job preservation: 'What is the best thing for me and my reelection?' " said Jenny Backus, a political consultant and a former spokeswoman for the Democratic National Committee.
Superdelegates are the 800 or so party and elected officials -- including all the Democrats in Congress -- who will attend the party's August convention and can vote for whichever candidate they choose.
They have become crucial to the nomination contest because it is now clear that, after all states and U.S. territories hold their primaries and caucuses to choose the other delegates to the convention, neither Obama nor Clinton will have enough delegates to clinch the nomination.
A groundswell of congressional endorsements for Obama in recent weeks has given him fresh momentum and has helped bolster his argument that he is the stronger candidate for the party.
But Clinton forces are pushing back to convince superdelegates on Capitol Hill that Obama will have a harder time winning a bruising general election campaign against Sen. John McCain of Arizona, the presumptive Republican nominee.
Her allies argue that Obama is untested and will be dogged by controversies including the inflammatory comments of his longtime pastor, the Rev. Jeremiah A. Wright Jr.
Rep. Brad Sherman (D-Sherman Oaks), a Clinton backer, gives her a clear edge in electability: "Her minister will not appear in McCain commercials."
Lobbying on Capitol Hill
Early in the Democratic race, Clinton held a big lead in Senate endorsements. But as Obama's campaign gathered momentum, he steadily gained public backers. When he was endorsed last week by Sen. Amy Klobuchar (D-Minn.), Obama tied Clinton with 13 colleagues each, according to a tally kept by Roll Call, a Capitol Hill newspaper.
At that point, the paper counted 80 House members for Clinton and 75 for Obama.
But dozens of lawmakers are still undeclared, and the importance of capturing their loyalty has turned Capitol Hill into a swirling political bazaar.
When Obama and Clinton returned to the Capitol in late March for a daylong series of budget votes, they had hours to chat up colleagues on the floor. Obama took the opportunity to talk health policy with Sen. Ron Wyden (D-Ore.), the sponsor of a big health bill, who is undeclared for either candidate.
Harold M. Ickes and Maggie Williams, top Clinton campaign aides, visited Capitol Hill several weeks ago to urge leaders not to commit to a candidate too early.
Former Sen. Tom Daschle of South Dakota, the onetime Democratic majority leader, has been calling former colleagues to tease out endorsements for Obama. Democrats are lobbying colleagues every time the House comes together for a roll call vote.
The presidential candidates are peppering even lowly House freshmen with calls.
Altmire said Obama first called him almost a year ago. Clinton has called him three times, Bill Clinton twice.
And Altmire was one of more than a dozen undeclared House Democrats who were invited to Clinton's home in mid-March for a reception and question-and-answer session over hors d'oeuvres.
One blunt question underscored how much lawmakers' thinking is shaped not just by high-minded reflection about who would make the best president, but by the cold-eyed political assessment: What does it mean to me?
Rep. Heath Shuler (D-N.C.), a freshman from a district that President Bush won in 2004 by 14 percentage points, asked Clinton to address concerns that in conservative districts like his she would not be "helpful" at the top of the ticket, Altmire recalled. Clinton responded by pointing to her success in GOP precincts in the New York and Arkansas primaries as evidence that the more people know her, the more support she draws -- even from Republicans.