Updated: 11:11 a.m.

Rep. Joe Sestak said Sunday that he was confident he would topple incumbent Pennsylvania Democratic Sen. Arlen Specter in Tuesday’s Democratic primary and called on Specter to endorse his candidacy when he does.

“I’m looking forward to Sen. Specter’s support after [Tuesday],” Sestak said during an interview on CNN’s “State of the Union.”

Sestak, who was elected to the House in 2006, has surged ahead of Specter in some polls in recent days and said he was confident he would best Specter, a 30-year veteran of the Senate, in part because of Specter’s decision to switch to the Democratic Party in April 2009.

“He’ll just say whatever he wants in order to keep his job,” Sestak said, adding that Specter was “willing to give up his vote for special interests.”

Sestak dodged the question of whether he would support Specter if the incumbent comes out on top Tuesday.

“He’s the poster child for what’s gone wrong in Washington, D.C.,” Sestak said.

Also appearing on the show, Specter defended his record in the Senate and his decision to change parties, saying he “had a clear shot at re-election,” if he had stayed “with the obstructionist Republican caucus.”

But Specter was widely considered vulnerable to a challenge from the right when he left the Republican Party last year and will face a tough race against Republican Pat Toomey if he does survive Tuesday’s primary.

Utah Sen. Bob Bennett, who lost last weekend at his state’s GOP convention, said Specter had “gotten himself into real trouble,” in part because of his decision to switch parties and predicted that Republicans had a good chance of picking up the seat, regardless of who wins the Democratic primary.

Bennett, who has not yet decided whether he will mount a write-in campaign to keep his seat, observed that there was a national trend of “anger against Washington” that could hinder both Specter and Sestak in the general election.

“In this anger, people do not differentiate between their representative in Congress and the federal government,” Bennett said.

Sen. Charles Schumer (D-N.Y.) predicted on NBC’s “Meet the Press” that Specter would pull out a victory on Tuesday.

“I’ll bet he wins by a little,” said Schumer, who chaired the Democratic Senatorial Campaign Committee in the 2006 and 2008 cycles.