Editor's note: Julian Zelizer is a professor of history and public affairs at Princeton University. He is the author of "Jimmy Carter" and of the new book "Governing America."
(CNN) -- Thursday's vice presidential debate will not receive nearly as much attention as the battles between Mitt Romney and President Barack Obama. After all, the debates between the vice presidential candidates are a bit like watching AAA baseball. Right now, most voters are focused on the people running for the highest office in the land.
Nevertheless, vice presidential debates have a colorful history. Although they don't do much to affect the results of the actual campaign, they can have an effect on the future of a candidate's career regardless of whether the ticket wins or loses.
In several cases, promising stars have been badly harmed by their performances, developing public perceptions that proved hard to shake.
With Vice President Joe Biden possibly considering a run for the presidency in 2016 and Wisconsin Rep. Paul Ryan widely considered to be one of the most promising stars of the GOP, both men have a lot to lose if their effort on Thursday does not go well.
In 1976, Sen. Bob Dole, R-Kansas, ripped into his opponent on many fronts, but he came off looking nasty and unnecessarily aggressive. Some of his statements were so controversial that they raised questions about whether he was fit to hold the office, particularly because voters were still leery from the nastiness of President Richard Nixon's White House.
During the debate Dole said that "If we added up the killed and wounded in Democrat wars in this century, it would be about 1.6 million Americans, enough to fill the city of Detroit."
Walter Mondale seized on the statement, saying that "Sen. Dole has richly earned his reputation as a hatchet man." That phrase stuck, even more than Dole's comments, and for many years Republicans remained skeptical that Dole could be an effective presidential candidate because of this negative image.
In 1988, Sen. Lloyd Bentsen, running with Michael Dukakis, picked apart Sen. Dan Quayle. The charismatic young conservative from Indiana was a fresh voice in the party, a politician who many observers thought could be a new leader for the GOP down the road. This was why Vice President George H.W. Bush selected him as his running mate.
When Quayle, who had stumbled through some gaffes early after his announcement, likened himself to President John F. Kennedy, Bentsen fired back: "I served with Jack Kennedy. I knew Jack Kennedy. Jack Kennedy was a friend of mine. Senator, you're no Jack Kennedy." The zinger played into fears that Quayle was a lightweight who could not handle the obligations of the presidency. While Quayle was on the winning ticket, his image took a big hit as a result of the debate and other events on the campaign trail.
In 2004, North Carolina Sen. John Edwards, running with Massachusetts Sen. John Kerry, also suffered from his encounter with a more experienced candidate, Vice President Dick Cheney. At the time, Edwards was one of the darlings of the Democratic Party, a photogenic senator who spoke emotionally about the issues of poverty and inequality, something that energized the party's base. But his performance in the debate was unsuccessful.
Cheney dug into Edwards, saying, "The first time I ever met you was when you walked onto the stage tonight," a statement highlighting the accusation that Edwards was more interested in advancing his career than politics and that he had constantly missed votes.
When Edwards brought up Cheney's daughter Mary, who is gay, to challenge his opposition to gay marriage, Cheney came back by saying, "Let me simply thank the senator for the kind words he said about my family and our daughter," ending Edwards' assault on the spot. Edwards' performance left many uncomfortable. The senator looked like a lightweight, and many came away more skeptical about whether he could handle the pressures of the presidency.
The 2008 debate between then-Sen. Joe Biden and Sarah Palin didn't have as many dramatic moments. Still it was harmful to Palin. The Alaska governor entered the debate with low expectations after a series of botched television interviews led voters to question whether she was really qualified to hold higher office.
During the debates, Palin did not do much to impress voters. Her decision to evade certain questions and give vague responses to others continued to fuel discussion as to whether she was out of her league.
Some scratched their head when she asked her opponent, "Can I call you Joe?" At another point she admitted that she "may not answer the questions the way the moderator and you want to hear."
The performance became fodder for "Saturday Night Live" comedians, with Tina Fey playing Palin, constantly winking and talking about being a maverick without any substance. When the segment ends, Fey asks: "Are we not doing the talent portion?" (A reference to Palin having been in the Miss Alaska competition.)
It might be that following the first presidential debate, where Mitt Romney dramatically turned the media narrative in his favor and walked away with a major victory, that interest will be greater than usual in this vice presidential debate, and a decisive victory either way could play some role in the campaign. But the chances are still slim.
Regardless, we do know that poor performances in vice presidential debates can harm the chances for a candidate to run for higher office down the road. Though they will obviously be focused on 2012, both Ryan and Biden will need to be careful not to act in ways that undercut their ability to run for the presidency four years from now.
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The opinions expressed in this commentary are solely those of Julian Zelizer.