U.S. Sen. Arlen Specter, D-Pa., cites an old axiom for political campaigns: "Run scared or unopposed."

But Specter, running for a sixth six-year term, seems confident in his chances to beat U.S. Rep. Joe Sestak in the May 18 Democratic primary election.

The latest Quinnipiac University Poll, released yesterday, may explain why. The poll shows the new Democrat holding a 53-32 percent lead over Sestak among likely Democratic voters. Sixty percent of those voters hold a favorable opinion of Specter while a similar percentage have not heard enough about Sestak to judge him.

That had Specter looking ahead yesterday to the general-election challenge from former U.S. Rep. Pat Toomey, the man he barely beat in the 2004 Republican primary before switching to the Democratic Party last year.

"The primary feels good, but I'm not taking anything for granted," Specter said. "Toomey is going to be tough, though, in the fall. I've beat him before and I know him and he's tough."

Quinnipiac was to release a poll today on how Specter matches up against Toomey. A similar poll last month showed Specter leading Toomey by 49-42 percent.

Sestak yesterday said it was a challenge to raise his name recognition among voters. That is typically done through televised campaign commercials.

"This election is going to go down to the last week or two," said Sestak, predicting a close-call finish as in the Specter-Toomey 2004 race. "We all know that."

Sestak, who had $5.1 million in the bank as of Dec. 31, would not say when his ads would start to air.

Specter, who had $8.7 million as of Dec. 31, said he would not run TV ads until Sestak does.

The poll also showed state Attorney General Tom Corbett with a commanding 58-7 percent lead over state Rep. Sam Rohrer in the Republican primary election for governor.

The Democratic poll results were a "three-way tossup," with Allegheny County Executive Dan Onorato leading among his party's likely voters with 20 percent, Montgomery County Commissioner Joe Hoeffel with 15 percent and state Auditor General Jack Wagner at 13 percent. State Sen. Anthony Hardy Williams, a late entry in the race, had 5 percent.

The poll showed that half of Democratic voters are undecided and that 70 percent who support a candidate could change their minds.

Peter Brown, assistant director of the Quinnipiac University Polling Institute, predicted:

"With that level of anonymity, anything is possible."