DANVILLE, KY. (USA TODAY) - The first striking thing about the vice presidential standoff Thursday between Joe Biden and Paul Ryan is how different the two men are.The second: how much they are the same.
The differences are obvious, starting with the generational contrast. Vice President Biden is 69 years old, a member of the so-called Silent Generation that came before the Baby Boomers. Wisconsin Congressman Ryan is 42, the first member of post-Boomer Generation X to be nominated by a major party on a national ticket.
The disparity in their ages is the widest of any national debate in the television age - bigger even than the one between Ronald Reagan and Walter Mondale in 1984, or between Dick Cheney and John Edwards in 2004.
Then there are their politics. Biden is one of the nation's senior Democrats, beloved by many of the blue-collar and Jewish voters who help make up the party's liberal base. Ryan is an up-and-coming Republican with a more reliably conservative history than running mate Mitt Romney and a stronger appetite for stirring controversy, especially on budget issues. That has made him a favorite of the Tea Party movement.
Those differences will be spotlighted on stage at Centre College in the sole debate between the vice presidential nominees, sandwiched between the first and second debates between the men at the top of the tickets.
But the similarities between Biden and Ryan also will shape their conversation, from their common roots in blue-collar America to long political careers that made each congressional royalty. In those ways, they resemble one another more than they do the presidential nominees at the top of their tickets.
That sets the stage for a debate that could be sharper, more immersed in policy details and more pointedly connected to the daily lives of Americans than the showdown between Obama and Romney in Denver last week.
That first presidential encounter wrote the marching orders for their running mates. Ryan is charged with articulating the case against the president's record and defending the Republicans' agenda, maintaining the momentum from what was the best debate performance of Romney's political career.
Biden's mission is the reverse, to prosecute the case against the GOP in a way his boss failed to do. For Obama, the weakest debate performance since he came on the national scene has cost him the narrow edge he had built nationwide.
To be sure, vice presidential debates typically don't matter much. Even the debate that had the clearest "winner" - Lloyd Bentsen after his memorable putdown of Dan Quayle as "no Jack Kennedy" - didn't rescue the 1988 election for the Democratic ticket. It was Quayle, not Bentsen, who was sworn in as vice president in January 1989.
This year, though, it's possible the running mates' debate could be of more consequence than usual in a campaign that is close and in flux.
So the showdown between Biden and Ryan?
Both are Catholics born in manufacturing towns in the Rust Belt that have seen economic struggles - Biden in Scranton, Pa., and Ryan in Janesville, Wis. - and that continue to shape the ways they relate to voters and the stories they tell on the campaign stump. Each is better at connecting with blue-collar workers from swing states than their presidential partners.
At a focus group Wednesday night in Columbus, Ohio, a dozen voters who haven't made up their minds which candidate to support or who are still open to persuasion talked about their views of all four nominees. The session, moderated by Democratic pollster Peter Hart, was sponsored by the Annenberg Public Policy Center at the University of Pennsylvania.
They were asked to describe the candidates in a word or two. For Ryan: "A good Catholic," "just a decent guy," "straightforward." One called him "inexperienced"; several said they didn't know much about him. They called Biden "funny," "entertaining," "empathetic." One said "embarrassing," perhaps a reference to the vice president's propensity for gaffes.
(They tended to draw warmer words than the presidential candidates sparked. Obama was described as "celebrity," "charismatic," "arrogant." Romney was "competent," "CEO," "inauthentic," "puppet master.")
The running mates' political careers are remarkably similar, though a generation apart. Both were interested in elected office from the start. Biden won his first election to the New Castle County Council in Delaware at age 28. At 28, Ryan also won his first election, to the U.S. House from Wisconsin's 1st Congressional District.
Biden stayed in the Senate for seven terms, including a tenure as chairman of the Senate Foreign Relations Committee, before becoming vice president. Ryan has served seven terms in the House and chairs the budget committee.
Then there's 2016. Biden has run twice for the Democratic presidential nomination, in 1988 and 2008. He doesn't deny an interest in running again in 2016. "I'll make up my mind on that later," he told CNN in an interview. Ryan is considered one of a rising generation of Republicans whose profile has been raised by this campaign, win or lose.
Which means it is at least possible that Thursday's debate won't be their last.