"We really would shock people if early in the evening of Nov. 6 it looked like Pennsylvania was going to come our way and actually did come our way," Romney said at the Union League. "That can happen."
Romney, who was hoping to raise between $3.5 million and $4 million from the wealthy donors at the fundraiser, said he was focused on the nation's economy.
"My priority is job creation and growing incomes," Romney told the donors. "My priority is not trying to punish people who have been successful."
Romney later told the public rally that he plans to win the state.
Rendell knocked Romney on Friday for comments the candidate made during a May fundraiser in Florida that was secretly recorded. There, Romney disparaged the 47 percent of Americans who don't pay federal income taxes, saying they see themselves as victims who want the government to meet all of their needs.
Rendell called that a "chance to look deep into Gov. Romney's soul" while pointing out that many of those people are retired, disabled veterans or hold jobs that don't pay enough to require federal income tax.
"It's a view of Gov. Romney's perception of America," Rendell said. "And it's dead-wrong."
Still, Rendell said it was "premature" for Romney to write off Pennsylvania as a lost cause.
"I think they should invest in Pennsylvania," Rendell said when asked about the Republican not running campaign commercials in this state.
An average of the last seven presidential polls in Pennsylvania, compiled by the website Real Clear Politics, shows President Obama with an 8-point lead here.
Gleason on Thursday said the state Republican Party plans to air a television commercial in western Pennsylvania that criticizes Obama on economic issues, including the unemployment rate and home foreclosures.
A party spokeswoman declined on Friday to provide specifics about where and when that ad would air.
- This report contains information from the Associated Press.
Contact Chris Brennan at firstname.lastname@example.org or 215-854-5973. Follow him on Twitter @ChrisBrennanDN. Read his blog at phillyclout.com.