HARRISBURG — Former Nebraska Sen. Chuck Hagel, a Republican who has broken ranks in the past with the GOP, gave Democrat Joe Sestak his second major endorsement from moderates in a week in his bid for a hotly contested Senate seat in Pennsylvania.

Hagel told The Associated Press on Monday that Sestak has demonstrated during his two terms in Congress that he puts the interests of the nation and his constituents ahead of his party.

"I think he's exactly what our country needs more of. I think he's what the Senate needs more of — courageous, independent thinking," Hagel said. "That's what the job is about. You are supposed to use your judgment."

Hagel refused to comment on the candidacy of Sestak's opponent, Republican Pat Toomey, a former congressman.

The men are seeking the seat long held by Sen. Arlen Specter, a Republican-turned-Democrat whom Sestak beat in the primary.

Hagel plans to announce his endorsement today at news conferences with Sestak in Pittsburgh and Philadelphia.

The two have military ties: Hagel, a moderate Republican, is a Vietnam War veteran, while Sestak is a 31-year Navy veteran who reached the rank of vice admiral before retiring in January 2006.

Like Hagel, Sestak is not afraid to buck his party. Until he won the May primary, Sestak received the cold shoulder from Democratic leaders.