Possible candidates include Sen. Bob Casey, State Treasurer Rob McCord, 2010 Democratic nominee Dan Onorato, U.S. Rep. Allyson Schwartz, former U.S. Rep. Joe Sestak and Montgomery County Commissioner Josh Shapiro. And there undoubtedly are more out there.
For now most are playing coy. But Burn said that the party must decide early on one candidate to avoid a costly and bruising primary battle.
"If we're going to do this, [we need to get] on the same page if we can, and we must so our nominee doesn't have to spend money in a primary," Burn said. "We can't come out depleted."
Burn said that the Democratic base was energized for a race. He noted the protests of Corbett's cuts to social services and education and the criticism of the voter-ID law, which requires each voter to show a valid form of identification at the polls in November.
This week's Daily News/Franklin & Marshall College Poll showed that more registered voters view Corbett unfavorably than ever before. Only 30 percent viewed Corbett "strongly" or "somewhat" favorably, while 43 percent viewed him strongly or somewhat unfavorably.
Insiders think that the most likely Democrats to get into the ring in 2014 are Sestak or McCord. Sestak - a former admiral in the Navy - has the time since losing a Senate bid in 2010. And McCord - who has an MBA from the Wharton School - holds a statewide office and could run without giving it up.
Sestak responded to Daily News email and phone messages through a staffer, making jokes, but not answering the question. McCord, who is running for re-election as treasurer, said in a statement that his attention is on his current race.
But - and this is a big but - could there be a scenario in which Casey decided to get into the game? Given his famous name as the son of a former governor, statewide popularity and status as a senator, he would be the big dog in the race.
"He would be the most formidable opponent," said G. Terry Madonna, a professor and pollster at Franklin & Marshall College. "I think the question is whether he wants to."
Larry Smar, Casey's campaign manager for his re-election effort, said Casey was dealing with the campaign at hand.
"He is fully focused on his work in the Senate and on running for re-election to the Senate. I've heard the rumors. This is just a Harrisburg parlor game," said Smar.
Of the other possible candidates: A spokeswoman for Schwartz said she was focused on her work in Congress, Shapiro declined to comment, and Onorato did not respond to requests for comment.
Beating an incumbent Pennsylvania governor is a tricky proposition. For one, it's never been done before. And Brian Nutt, the political adviser who ran Corbett's 2010 campaign for governor, noted that predicting now what will happen in 2014 is about as easy as winning the lottery.
"We're talking about a poll in September of 2012, and the election isn't for another 26 months," Nutt said. "In politics, that's an eternity. A lot of different things can happen between now and then."
Kevin Harley, Corbett's spokesman, said, "Leadership is not a popularity contest. Tom Corbett inherited a financial disaster from Ed Rendell, and he is returning Harrisburg from a culture of tax-and-spend to build-and-save. It's not always easy."
Governors were limited to a single term until the state law was changed in 1968, and it's not unusual for incumbents to struggle early in their first term.
"Every incumbent with the exception of Dick Thornburgh [who served from 1979 to 1987] has had a tough first year and a half," said Madonna. "We have to be very careful looking at job performance at this point."
Until this year's general election closes, no one will say much. So most are playing a wait-and-see game, trying to suss out the field and wondering what Corbett will look like closer to the election.
"It's always a game of guessing," said Christopher Borrick, a political-science professor at Muhlenberg College. "Now he looks vulnerable. How vulnerable is he going to be in the fall of 2013? That's the question."
- Staff writer Chris Brennan
contributed to this report.
Contact Catherine Lucey at firstname.lastname@example.org or 215-854-4172. Follow her on Twitter @PhillyClout. Read her blog at phillyclout.com.