He alluded to his Pennsylvania roots several times, he told homespun stories, and, for about 90 minutes, Vice President Biden charmed a pep-rally-friendly crowd Friday at Central Bucks High School West in Doylestown.

He defended the Obama administration's performance on the economy, mentioned the pullout of U.S. troops from Iraq, and delivered a populist speech on controlling skyrocketing tuition costs.

But if his visit had the trappings of a campaign appearance in a potentially pivotal region - and once again the presidential and vice-presidential candidates may qualify for "frequent visitor" passes to Pennsylvania by November - the crowd was no less welcoming of the star attraction.

"We're very excited," said Jess Circuit, a senior and member of the National Honor Society. "This is a big deal."

"I'm the first guy in my family to go to college," Biden told the 1,600 people, mostly juniors and seniors, who had jammed into the school gymnasium.

He said that he was acquainted firsthand with the high cost of college - that helping pay tuition for his three children contributed to his relatively low net worth. Biden's worth - less than $750,000 - is much less that President Obama's ($7 million) or Secretary of State Hillary Rodham Clinton's ($31 million), according to the Center for Responsive Politics.

On average, annual tuition at a private college has jumped to $32,184, a 25 percent increase in the last decade. Public college costs are up 37 percent, to $12,874.

"Parents are questioning if the cost is worth it," said Biden. "That's never happened before."

He said the administration was continuing to look at ways to persuade schools to bring down costs. The president recently held an unprecedented meeting with private-college presidents.

Biden suggested that colleges and universities were at fault to some degree for investing so much in buildings and professorial salaries in an effort to draw top students.

After speaking for a half-hour, Biden answered questions for 40 minutes and spent an additional 20 minutes greeting students and posing for pictures.

Among those impressed with Biden's performance was a member of the enemy camp: U.S. Rep. Michael Fitzpatrick (R., Pa.), who wrestled back his congressional seat from Democrat Patrick Murphy in the 2010 election.

"His speech was excellent," said Fitzpatrick, "and he was very engaging with the students."

Less impressed was Pennsylvania GOP Chairman Rob Gleason, who said in a statement: "Joe Biden is in Pennsylvania once again to camouflage the Obama administration's failure to create jobs and get our economy moving again."

"These are like little proxy wars," said William Rosenberg, professor of political science at Drexel University. "This is going to happen continually between now and the general election. This is going to happen in all the battleground states."

Bucks County, where Democrats now hold a slight registration edge, could be particularly important to the Pennsylvania outcome. Democrats made significant registration gains in the county in the last year, Pennsylvania State Department figures show.

Biden did not discuss politics overtly on Friday, and when asked to comment on alleged GOP efforts to discourage voting among groups traditionally friendly to his party, he said, "I'd rather not talk about Democrats and Republicans today."

He praised the school for its roster of advanced placement classes and 100 percent graduation rate, and told the students they were part of American's "greatest generation."

But the visit is part of a larger strategy, said Rosenberg.

The Republicans are "hogging the camera" with their nomination race. Thus, the Democrats, he said, feel a need to say, " 'We're here, too.' "