Sen. John McCain told ABC's Jake Tapper Sunday.

"I know enough about what strategy and tactics are about. If you tell the enemy that you’re leaving on a date certain, unequivocally, then that enemy will wait until you leave," he said.

Sen. Joe Lieberman also hopes that as the deadline nears Gen. David Petraeus and Obama will change their minds.

"The President has come some distance now in the last couple of weeks and clarified that. Whatever we do in July of 2011 will be based on conditions on the ground at the time," he told Fox News' Major Garrett Sunday.

"You know, the President made the right decision last December that America has a vital, national security interest on the line here in Afghanistan. We've got to win it. And therefore, you don't put that on a timeline," said Lieberman.