Now let me make it clear that I'm arguing from a standard American liberal view.
I think Obama has been more true to the principles of liberalism than most modern presidents and despite his flaws, has done a lot.
-Obamacare and pre existing conditions.
-withdrawal from Iraq (I know Bush started this)
-I think he's pretty good on foreign policy. This situation is complex and he's being careful. More so than Bush.
-he's doing amazing with Cuba and Iran.
-overall, he makes us look good to the world and we get respect. People around the world like Obama.
Also, his personality certainly helps. Even when he does things I disagree with he can be charming, witty, and funny when talking.
He's very charismatic and has been great at presenting himself (like the limp hand move he did to Castro to not associate with doing the salute).