HARRISBURG -- The gubernatorial election has been over for five days, so, naturally, it's time to start thinking about 2010.

True, it's a long way off, and we're nowhere near another onslaught of nasty television commercials, but there already is speculation about what the match-up could be in four years.

Some see the early line as a race between two Western Pennsylvania heavyweights, Democrat Dan Onorato, the chief executive of Allegheny County, and state Attorney General Tom Corbett, a Shaler Republican.

Or maybe it'll be an east-west match-up featuring state Auditor General Jack Wagner, a Pittsburgh Democrat, and either former Lt. Gov. Bill Scranton, of Scranton, who dropped out of this year's GOP race, or ex-Congressman Pat Toomey, of the Lehigh Valley, who narrowly lost a Senate Republican primary race in 2004.

Could it even be a rematch of the nasty political brawl between Democrat Bob Casey and Republican Rick Santorum, only this time for governor?

Mr. Casey, who defeated Mr. Santorum and will become a U.S. senator in January, has long wanted to follow in the footsteps of his late father, Gov. Robert P. Casey, who served from 1987 to 1995. But now that he's been elected to the Senate, "he has pledged to serve out his full six-year term," campaign spokesman Larry Smar said. And Democrats who worked hard to wrestle the seat away from Republicans are unlikely to agree that an incumbent can step out of the Senate, unless Mr. Casey makes some rather large mistakes.

Still, some skeptics have noted Mr. Casey's tendency to run for a lot of offices -- auditor general, state treasurer, U.S. Senate -- and say they wouldn't be surprised if he ran for governor.

"Being governor is the job Bob Casey has always wanted," Harrisburg political analyst Charlie Gerow said.

Some people also think Mr. Santorum could be back in the fray four years from now.

Despite his loss Tuesday, Mr. Gerow predicted, "Rick won't make a Nixonian statement like 'You won't have me to kick around anymore.' I think he'd be a viable candidate for a number of offices. Like him or not, he's a very talented guy. If he runs for governor, he'd be formidable.''

But another Harrisburg analyst, pollster Michael Young, disagrees. He sees Mr. Santorum as more likely to consider running for president in 2008 than governor in 2010. "He could be plausible as a presidential candidate," Mr. Young said.

As for the race of governor in 2010, state Democratic Party spokesman Abe Amoros said, "I've heard Dan Onorato mentioned, as well as Jack Wagner and Lehigh County Executive Don Cunningham," a former state secretary of general services under Gov. Ed Rendell.

"But it's so early," Mr. Amoros added. "We have to study Tuesday's election results and then we have to focus first on the judicial races in 2007 and then the presidential race in 2008."

And, despite his lopsided defeat Tuesday, don't forget about football player-turned-politician Lynn Swann, said Thomas Baldino, a political science professor at Wilkes College.

Mr. Swann, 53, is still young in political terms, Mr. Baldino said. "I think he's established some credibility as a candidate with the public and Republican Party leaders. He will have earned at least some consideration for another go" at governor.

As for Republicans in 2010, Mr. Gerow said, "I'd rate Bill Scranton as having the pole position, the inside track, right now. He and Tom Corbett are often mentioned as strong candidates.'"

Others who might be interested, on the Democratic side include former state Treasurer Barbara Hafer, and, for Republicans, "the three Ps," meaning state Sen. John Pippy, of Moon; state Sen. Jeffrey Piccola, of Dauphin County; and House Speaker John Perzel, of Philadelphia. Mr. Gerow said Jim Matthews, the GOP lieutenant governor candidate this year, was another possibility.

Another formidable Republican who shouldn't be counted out is U.S. Rep. Melissa Hart, of Bradford Woods, who was ousted by newcomer Jason Altmire on Tuesday. Or, possibly, U.S. Rep. Jim Gerlach, R-Chester County, who held off a tough Democratic challenge.

Pittsburgh political analyst Bill Green said someone from Western Pennsylvania was likely to be in the 2010 gubernatorial mix. He said many candidates for governor, especially Republicans, come from Western Pennsylvania, such as Gov. Dick Thornburgh in the 1980s, Gov. Tom Ridge in the 1990s or former Attorney General Mike Fisher, who lost to Mr. Rendell in 2002.

As for Mr. Corbett in 2010, Mr. Green quipped, "He's already the A.G., which stands for 'aspiring governor.' " And concerning Mr. Onorato, "I think he would certainly entertain the idea of running for governor."

Mr. Green said the Allegheny County chief executive is often called the third most powerful official in Pennsylvania, after the governor and the mayor of Philadelphia.

Speaking of the latter, Mr. Gerow included the next mayor of Philadelphia, if that person compiles a strong record of achievement after winning office next November. At least a half dozen candidates, all Democrats, are considering a primary run in May.

"If you get a top-tier mayor from Philadelphia, you'd have a power base from which to operate," Mr. Gerow said. And everyone knows that the current governor, Democrat Ed Rendell, was mayor of Philly for eight years in the 1990s.

Officially, of course, it's poor form for the candidates to be talking about a race four years off. They like to appear focused on their current office. Mr. Corbett has been keeping himself in the public eye with frequent news conferences about busting drug lords and child pornographers.

"He plans to seek re-election in 2008 and is working hard for the citizens. That's where all his energy is directed," spokesman Kevin Harley said. "He will continue to pursue drug dealers and protect our children from child predators."

Kevin Evanto, an Onorato spokesman, sounded remarkably similar. "Dan is focusing only on his race for re-election as county executive in 2007," he said.

Mr. Wagner was similarly evasive. "There's always a possibility [of running in 2010], but it's far too early to focus on the governor's race," he said. "I am concerned about a multitude of issues facing the state now. A lot can happen in four years."

While it's too soon for Mr. Rendell to take sides for 2010, he has had nice things to say about Mr. Onorato's leadership in Allegheny County.

"Dan Onorato is an incredibly effective executive and he's a rising star in the Democratic Party," Mr. Rendell said, but added, "To speculate now on an election in 2010 is not productive."

Mr. Wagner hasn't been as close to Mr. Rendell. Mr. Wagner ran for lieutenant governor in 2002 on a Democratic primary ticket that included Bob Casey for governor. Mr. Casey lost to Mr. Rendell in the May 2002 Democratic primary while Mr. Wagner was losing to Lt. Gov Catherine Baker Knoll.

A lot of candidates being mentioned now are obviously long-shots. But how about this, a "mystery candidate." Mr. Gerow said he wouldn't be surprised if someone with no background in politics but with a successful career in another field, especially business, were to emerge.