After a nearly trillion-dollar federal stimulus, historic health care reform legislation and two confirmed liberal Supreme Court justices, one might think the American left would have to be somewhat satisfied with President Barack Obama, at least as a presidential nominee.

But Independent Vermont Sen. Bernie Sanders is not. In an interview with liberal talker Thom Hartmann on Friday, Sanders spoke out very aggressively about the possibility of Obama facing a challenge from his left for the Democratic nomination.

“Well, at this point I have not,” Sanders said. “But I am now giving thought to doing it. You know, I think you know the names out there as well as I do. And I think the American people have got to be engaged. It’s not just me or anybody else here in Washington. There are a lot of smart honest progressive people who I think can be good presidents.” (Bernie Sanders says it’s time to bring the troops home)

Sanders said such a challenge was necessary since in his estimation, the president had begun to take his position as the party leader for granted.

“And I think one of the reasons President Obama has moved as far to the right as he has is he thinks he can go all the way and no one will stand up to him,” Sanders continued. “So, Tim I don’t want to tell you more than that but this is an issue I am – we are beginning to talk about a little bit.”

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