He's been both extolled and mocked as "Scranton Joe" or "Sheriff Joe," but what about "President Joe"?

After spearheading the last-minute "fiscal cliff" deal and leading the White House effort to stem gun violence, Vice President Biden has ignited buzz about a 2016 presidential run.

Some have dismissed Biden's presidential prospects, saying his propensity for gaffes and his cartoonish antics disqualify him from occupying the highest office in the land. And his age is a factor -- Biden would turn 74 shortly after Election Day 2016.

However, even conservatives concede Biden has recently proved to be more than comic relief -- and possibly a serious presidential contender.

"He's been a sideshow for much of this administration," said former Rep. Bob Walker, R-Pa. "But of late, the vice president has put himself in a different light. He's shown that he's willing and capable of talking to Republicans and getting things done."

When talks broke down between Senate Majority Leader Harry Reid, D-Nev., and Senate Minority Leader Mitch McConnell, R-Ky., the senior Republican turned to Biden to break the impasse. If the White House produces new gun restrictions, Biden will receive wide praise from progressives for bridging the divide between gun control advocates and firearms enthusiasts.

Outgoing Secretary of State Hillary Clinton is widely viewed as the front-runner for the next Democratic presidential nomination. But with her recent health scare, many wonder whether she will stay on the sidelines, effectively opening up the Democratic primary to the likes of Biden, New York Gov. Andrew Cuomo and Maryland Gov. Martin O'Malley.

But for all the recent credit given to Biden, the vice president is still capable of some head-scratching moments.

"I'm shooting for Tuesday," Biden said last week when asked about his target date for finalizing gun proposals to present to President Obama. "We know there is no silver bullet," he added.

Obama chose Biden for what some saw as his foreign policy expertise and his unique ability to connect with blue-collar voters. And Biden's feistiness in the vice presidential debate helped appease Democrats who questioned whether Obama lacked the fire to take on Republican presidential candidate Mitt Romney.

"I've never been worried about the gaffe charges," Democratic pollster Margie Omero said. "This is who he is -- it makes him real. He's known for his loose talk. It's not like people are just discovering this about him."

Biden would still face damaging public perceptions were he to pursue the presidency. According to a recent Pew poll, 40 percent of respondents said "idiot" was the first word that came to mind when thinking of Biden.

No matter how Biden polishes his resume during a second Obama term, another unavoidable factor could torpedo a bid for the White House, analysts said.

"I just don't see it, considering his age," Democratic strategist Keir Murray said of the 70-year-old. "Anything is possible, but his age already makes it questionable. Add four more years -- that's a long time."

Another Democratic media consultant gave an even more blunt assessment.

"No, no, no; I don't have time for that type of cleanup," he said before immediately hanging up the phone.