WASHINGTON -- He was a special guest at a tea party at Sen. Hillary Rodham Clinton's house. Bill Clinton has called him three times. Sen. Barack Obama has been sending him personal e-mails since June.

Rep. Jason Altmire, an uncommitted superdelegate in the Democratic party, has become the center of attention as the Pennsylvania primary nears. Altmire, a first-term Democrat from Mccandless, is being heavily courted by the rival Democratic presidential campaigns. Though Altmire is a newcomer to Washington, D.C., his politically moderate 4th Congressional District is often viewed as a political "ground zero," a must-win, for Democrats running statewide campaigns in Pennsylvania.

Altmire said both campaigns are ratcheting up their efforts to win his endorsement as the primary approaches. Altmire, in an interview Wednesday with wpxi.com, said he was heavily lobbied by Clinton supporters from Arkansas and New York during the tea party at Clinton's Washington home. Altmire said, "There were 17 of us `uncommitted superdelegates' there. They were really trying to put the screws to us and get us to commit to Senator Clinton."

Altmire described a recent phone call from Bill Clinton. He said the former president was "giddy" and excited by Senator Clinton's performance in Texas and Ohio. But Altmire said he objected when Bill Clinton began making negative comments about Obama and Obama's campaign.

Altmire said, "Senator Obama has been in constant contact with us. He took a much more longterm view of this from the beginning, whereas the Clintons never thought Pennsylvania was gonna be important. They kind of ignored us for awhile and now they're a little bit late to the game."

In recent days, other previously uncommitted Pennsylvania Democrats announced endorsements. Veteran Johnstown Democrat John Murtha threw his support behind Clinton. Democratic Sen. Bob Casey endorsed Obama. Altmire said he'd rather hold off until after the primary results are tabulated. He said, "Judging from the calls we've been taking, people would rather I just stay out if it and let the process take care of itself. Then, we'll add the outcome of the vote in my district and the state -- to the list of things I'm going to consider when I make my decision."

It's widely believed superdelegates will have the ability to determine the ultimate nominee. Obama is expected to finish the primary season with more pledged delegates, which makes the role of uncommitted superdelegates more important. Will Altmire be willing to formally side with Clinton, even if Obama wins more pledged delegates? Altmire said, "That's a question I've asked Senator Clinton directly. If Senator Obama is ahead on delegates, popular votes, and more states, why should a superdelegate switch sides at that point and go against the will of the people? She has an answer for it, but that's going to be a very difficult vote for me to make."