Both were political science majors there in the mid-1960s — Kyl graduated in 1964 and Pederson graduated in 1965 — but even then they circulated in different crowds.
Kyl rushed a fraternity. He studied the Constitution and the Federalist Papers, occasionally taking his girlfriend on dates to the science library. "She now happens to be my wife," said Kyl, Arizona's junior senator.
Pederson, now Kyl's opponent in the Nov. 7 election, worked in the kitchen of a sorority. Though he entered college a Goldwater Republican, Pederson left a Democrat.
"There were a lot of protests in the streets," Pederson said. "It wasn't just about the (Vietnam) war ... it was about unfairness, it was about justice, social justice, criminal justice. I got caught up in all of that.
"I just made the determination that the Democratic Party was more in line with what I thought going through school."
Both men say their university experiences were key in shaping their political views. Four decades later, Kyl and Pederson are giving voters a distinct choice as Arizonans choose who should represent them in Washington.
Both sides have been waging expensive campaigns to sway the hefty chunk of independents and moderate voters in Arizona. Together, they've spent more than $11 million on television ads that have sometimes bent the truth. Recent polls have consistently shown Kyl in the lead.
Pederson argues that after so many years in Congress, Kyl has lost touch with Arizona voters and doesn't recognize how the state has changed over the years. He says the incumbent senator has become too cozy with Bush, oil and pharmaceutical companies.
Pederson says he'd inject some "business sense" into Congress and judge ideas on whether they'd work — not which party sponsored them.
Kyl focuses on Pederson's inexperience in political office and claims his ideas simply were forwarded from Democratic Party liberals. Kyl has repeatedly pointed out that Pederson is a wealthy shopping mall developer who has bankrolled his campaign with about $8 million of his own money.
The difference between the two candidates, Kyl says, is that after college "one made a lot of money, the other went into public service."
As the ad war escalated after the Sept. 12 primaries, Pederson and Kyl have lobbed accusations at each other, forcing the other side to buy an ad and "set the record straight."
In his ads, Pederson says Kyl wants to criminalize abortion, even in cases of rape, incest and when the woman's life is in danger. He cites Kyl's support for two resolutions while serving in the House of Representatives in the late 1980s. Those resolutions never came to a vote.
Kyl disputes that claim. He has said over the years to the AP and other news organizations that he would make an exception for abortion in cases that involved rape, incest or threats to the woman's health.
In one of Kyl's ads, the senator accuses Pederson of "pushing a trillion dollar tax hike." He supports this using a statement Pederson made while criticizing the repeal of the estate tax, a policy that Pederson says would add $1 trillion to the federal deficit.
According to Annenberg Political Fact Check, repealing the estate tax would cost $21 billion using 2004 figures, much less than both men estimate.