You mean like they have the last 4 years /s Obama has already proved he can do anything he damn well pleases and no repub or no demo is going to stop him.
Not true. He was forced to extend the Bush tax cuts. Even the dems wouldn't let him pass cap-and-trade. They wouldn't let him pass single payer health care, so he had to go with the mandate scheme. And that might get overturned by the courts. He's doing a lot of bad stuff, obviously, and stopping us from doing a lot of good stuff. But literally 5 less RINOs in the Senate and we would have been able to block Justice Kagan. He is being held back on some fronts and with more power in Congress we can do more. It's even theoretically possible to get enough votes to override a presidential veto.
There is the flavor of that, but I don't think it's entirely accurate. He did a lot more damage in 09 and 10 (Obamacare, etc.) than he did last year, after his disastrous midterms. You might make the argument that he's intentionally backing off as he nears reelection ("after my last election, I'll have more flexibility" -- you have to be flexible to bend over and grab your ankles), but it doesn't seem that way from what I've seen. As feckless as the Congressional GOP is, they have made a difference.