Barack Obama's "Road to Change" led him to State College Sunday, where he spoke to a historic crowd of nearly 22,000 students and community members at Old Main's steps.

The speech was one of several scheduled stops throughout Pennsylvania for Sen. Obama, D-Ill.

The presidential hopeful was introduced by Penn State cornerback Lydell Sargeant and Sen. Bob Casey, D-Pa.

"Pennsylvania likes an underdog, and Pennsylvania likes a fighter; and that's what we have in Barack Obama," said Casey, who endorsed Obama on Friday.

During the speech, Obama addressed issues such as the Iraq War and bringing change to the country and its economy -- while mixing in a few jokes along the way.

"I just talked to your husband," Obama said to Sue Paterno, "and we've decided that after I get this whole thing settled, I'm going to have to come back and a watch a football game."

Obama mentioned connections between his candidacy, Penn State and the man whose likeness rests in Old Main.

"I stood on the steps of the old state capitol in Springfield, Ill., the building where Abraham Lincoln served for most of his life before he went to Washington," he said. "And I know that there is a part of Abraham Lincoln in this building. This college is a land-grant college, and it was founded by that man from Illinois."

Speaking about what motivated him to run for president, Obama referred to "what Dr. [Martin Luther] King [Jr.] called the fierce urgency of now," adding "because I believe there is such a thing as being too late."

Krishna Esteva, a senior at State College Area High School, said he shook hands with Obama.

"It's almost a religious experience," he said. "We knew it was going to be big, but I was just looking out on this sea of faces that extended into the distance."

Obama linked the costs of the Iraq War with a lack of investment to the United States infrastructure.

"We are spending $10 billion a month in Iraq ... Imagine if we were spending $10 billion right here in the United States of America rebuilding roads, rebuilding bridges, laying broadband lines, putting Americans back to work," Obama said. "That is what we should be doing. That's what we will be doing when I'm president of the United States of America."

Antoinette Houston, a State College resident who attended the rally with two of her children, said she already liked Obama before listening to the speech.

"That just sealed the deal," she said. "He has the best policies. He seems like a great family man ... he seems like he cares about what's going on in my life."

Obama also spoke about how his judgement would help him further national security.

"Keeping you safe is not just answering a phone call at 3 in the morning," he said. "What you want is good judgement at the other end of that phone."

In an e-mail, Casey wrote that "students today felt Obama's authenticity and his strength" during his visit to the campus.

Greg Stewart, co-chair of the Obama field team, met with Obama along with several members of the student group supporting him.

"We got to meet him before the event," Stewart said. "He was very pleased to be here."