Two more surveys of Pennsylvania voters confirm the early momentum for businessman and former state revenue secretary Tom Wolf in the Democratic race for governor while underscoring the chronic challenges Gov. Tom Corbett faces in defending his seat.

By the whopping margin of 55 percent to 34 percent, voters say the Republican incumbent does not deserve re-election, according to a Quinnipiac University poll released Wednesday. Mr. Corbett comes up on the short end of trial heats against each of his potential Democratic challengers, though by relatively small margins in some cases.

For now, after his weeks of heavy television advertising, the Democrats’ strongest contender is Mr. Wolf, who topped Mr. Corbett by a virtual landslide, 52 percent to 33 percent, according to the poll.

A Franklin & Marshall College poll, which was also released Wednesday, showed Mr. Wolf with a wide lead over his party rivals. Mr. Wolf led with 36 percent of the Democrats surveyed, followed by state Rep. Allyson Schwartz of Montgomery County, 9 percent and state Treasurer Rob McCord, at 3 percent. Two former state environmental secretaries, John Hanger and Katie McGinty, were still farther back at 1 percent each.

The F&M poll found, however, that 48 percent of Democrats are still undecided on their nominee.

Those results were broadly consistent with the finding of a Harper Polling survey, released Monday, which showed that Mr. Wolf led his party rivals with 40 percent of the Democratic votes, nearly three times the total of his closest competitor, Ms. Schwartz. Competing campaigns had sought to dismiss the significance of that lead, arguing it was the transitory product of his near monopoly on the airwaves. The only other Democrat who has aired commercials is Ms. McGinty, and her ad purchases so far have been a small fraction of Mr. Wolf’s. Some findings of the F&M survey support that analysis, although they do not suggest his early lead will be easy to overcome.

Two-thirds of the Democrats surveyed by F&M had seen a television ad on the race. Of those, 56 percent supported Mr. Wolf. But the poll’s analysis pointed out that among the minority of Democrats who could not recall seeing an ad, Ms. Schwartz held a lead of 13 percent to 11 percent. Those who hadn’t seen a commercial were also far more likely to be undecided in the race — 68 percent compared to 48 percent among all Democrats and the 33 percent who remained undecided after having viewed a Wolf commercial.

On Friday, most of the Democratic candidates will gather for a debate in Harrisburg, their first joint appearance since the trio of polls anointed Mr. Wolf as the new front-runner. So far, their debates and forums have been relatively civil affairs, but the new survey data suggests his rivals may now be tempted to take a more aggressive approach to the businessman who has contributed $10 million to the campaign.

Mr. Wolf had the highest approval rating among the Democrats tested in the F&M poll, but the party’s voters continue to have a fairly vague sense of their field. Forty-four percent said they held a favorable view of Mr. Wolf, just 3 percent, unfavorable; 7 percent said they were undecided; but, several weeks into his ad campaign, a plurality, 47 percent, said they didn’t know enough about him to express an opinion.

Voters’ views on other Democrats were even less well formed. Sixty percent held no opinion of Ms. Schwartz’s favorability. Even though Mr. McCord has won two statewide races for treasurer, four out of five voters said they didn’t know enough about him to express an opinion, while 86 percent didn’t know Ms. McGinty.

The F&M survey of 548 registered Democrats was conducted from Feb. 18 to 23. It did not include questions about former state Auditor General Jack Wagner, who did not enter the race until his quiet announcement late last week. In the Quinnipiac survey, however, he was among the Democrats who ran ahead of Mr. Corbett. He beat his Allegheny County neighbor 44 percent to 37 percent, a margin in the same ballpark as the other Democrats with the exception of the surging Mr. Wolf.

In the other trial heats, Ms. Schwartz topped Mr. Corbett, 44-38; Mr. McCord, 43-36; former DEP Secretary John Hanger, 40-37; and Ms. McGinty, 40-38.

First Published: February 26, 2014, 11:41 a.m.
Updated: February 27, 2014, 5:07 a.m.