I think he’s just intoxicated, or possibly senile.

Via Politico:

Joe Biden summoned more than 200 Democratic insiders to the vice presidential residence Sunday night to chat about the 2012 triumph — but many walked away convinced his rising 2016 ambitions were the real intent of the long, intimate night.

“I took a look at who was there,” said longtime New Hampshire state Sen. Lou D’Allesandro, “and said to myself, ‘There’s no question he’s thinking about the future.’” [...]

“He’s intoxicated by the idea, and it’s impossible not to be intoxicated by the idea,” said a Democrat close to the White House. And the intoxication is hardly new. Officials working on the Obama-Biden campaign last year were struck by how the vice president always seemed to have one eye on a run, including aggressively courting the president’s donors. Obama aides at times had to actively steer Biden to places where he was needed — like Pennsylvania — because he kept asking to be deployed to Iowa, New Hampshire and other early states.