Even if Obama was pressed on this, he'd blame it on Bush.
He let four Americans die, and out and out lied to the American people about this. For three weeks he had his people lie to the media about the video, and lied himself about it.
This is much more serious than Watergate. Obama has used the State Department, the DoD and the CIA to cover for a monumental screw-up that resulted in the deaths of our ambassador and staff. That's huge.
There is absolutely nothing bad Obama can do that will be covered by the press, or investigated by congress or law enforcement.