Check out the faces of the four other people in the image.  The middle-aged angry white man sitting next to him nursing his mug of draft beer.  The 30 something female executive with a martini who appears to be smiling.  The frizzy haired grandmother who seems to be either frowning or shocked.  Not sure how to read the bartender's facial expression.  Maybe 'pipe down, this is a quiet establishment.' 

And the central character, sipping either wine or a Belgium ale, is clearly happy to have the president back off of the life support he was on at the first debate.  But I wonder if the cartoonist drew him as a donkey because he self identifies as a partisan or because anyone who roots for the success of our sitting president would be seen in the eyes of the world as a partisan ass?