He challenged his democratic opponents to vote yes to ban pork barrel spending for one year.
"I have fought against it I will succeed in stopping it and stop the earmarking which Senator Obama and Senator Clinton have engaged in pork barrel spending, I never have," he said.
McCain attended a private fundraiser in Rittenhouse Hotel tonight. He will hold a town hall meeting at the Springfield Township Country Club on Friday morning.
While McCain and voters have witnessed the two democrats engage in some caustic exchanges the past few months, Clinton and Obama were seen chatting on the Senate floor on Thursday. At one point Obama gave the NY Senator a pat on the back, but in Pennsylvania, their spouses were hard at work campaigning.
Michelle Obama read Dr. Seuss to students at the Children's Arc at St. George's Episcopal Church in Ardmore.
Later, she sat down with some of the student's mothers to listen to their concerns about daycare and healthcare and making choices.
"I decided to go back to work just because of the benefits. Half my salary goes to my daycare," said one mother.
The Obamas have two daughters, ages 9 and 6.
"I am struggling every day to try to keep it together," Obama said. "I grew up thinking you could have it all. ... I'm still trying to figure out how do you do it."
In Canonsburg, Bill Clinton held a rally for his wife. She has scheduled two campaign stops in Pittsburgh on Friday. She also plans to appear at the city's St. Patrick's Day parade on Saturday.
Obama and Clinton have accepted invitations to debate in Philadelphia next month.
ABC News will host the debate on a date still to be determined.
Pennsylvania voters go to the polls April 22 for the primary, a contest with 158 delegates at stake.
