Sen. Arlen Specter (D-Pa.) and Rep. Joe Sestak (D-Pa.), who are engaged in a tough Senate primary, each offered their congratulations to President Barack Obama for his Nobel Peace Prize awarded today.

Obama surprisingly earned the prize early this morning, becoming only the third sitting president to win the award.

Specter, who switched party affiliations earlier this year, and Sestak have spent much of the campaign appealing to the Democratic base.

The two lawmakers tweeted this morning:

Specter: Congratulations President Obama on winning the Nobel Peace Prize, and thank you for your commitment to diplomacy.

Sestak: Congratulations to President @BarackObama for being awarded the Nobel Peace Prize on your efforts in strengthening global diplomacy.

The Nobel Committee announced it was honoring Obama for his "extraordinary efforts to strengthen international diplomacy and cooperation between peoples."

Obama was inaugurated just two weeks before the deadline for the 2009 award.