They sit on top of Democratic presidential primary polls, but as Nate Silver notes, those numbers may not yet reflect the age issue that will be an obstacle for both former Vice President Joe Biden and Sen. Bernie Sanders, I-Vt. Though both men will likely have to confront the issue at some point, it will likely be a bigger challenge for Biden to overcome.
At the outset, it’s worth making clear that age should be considered a legitimate issue for both candidates. If elected, Biden would be 78 on Inauguration Day, and Sanders would be 79. By way of comparison, Ronald Reagan, the oldest president ever to serve, was still weeks away from reaching 78 when he left office. When Reagan made the famous quip in a 1984 debate about opponent Walter Mondale’s “youth and inexperience,” he was still only 73.
That said, there are two ways in which age can manifest themselves in a campaign. The most direct would be some sort of health scare, or an unfortunate fall, like Bob Dole’s in 1996. But if older candidates can avoid such news, and otherwise seem energetic and vigorous, it’s possible they could get past a more direct public reckoning with their ages.
The more indirect way that older candidates can be hurt is if their age can become representative of having old and outdated ideas. This makes older candidates particularly vulnerable to younger rivals promising change. It’s in this more indirect way that Biden will have the bigger challenge.
Biden has been in the political arena since the 1970s, and during that time he was a traditional mainstream liberal who often tried to position himself as a centrist on some issues. In a drastically changed Democratic Party, his past has come under fire from liberals, and he’s been forced to apologize multiple times for his previous positions or behavior.
In contrast, Sanders has for decades been one of the most liberal members of Congress, and the party has moved closer to him.
Just take the issues highlighted in a recent column from Michelle Goldberg of the New York Times, arguing it was the “wrong time” for Biden.
“Beyond gender, on issue after issue, if Biden runs for president he will have to run away from his own record. He — and by extension, we — will have to relive the debate over the Iraq war, which he voted to authorize. He’ll have to explain his vote to repeal the Glass-Steagall Act, which, by lifting regulations on banking, helped create the conditions for the 2008 financial meltdown. (Biden has called that vote one of the biggest regrets of his career.) In 2016, Hillary Clinton was slammed for her previous support of the 1994 Violent Crime Control and Law Enforcement Act, which contributed to mass incarceration. Biden helped write the law, which he called, in 2015, the ‘1994 Biden crime bill.'”
Yet on those issues, Sanders’ record is much more closely aligned with prevailing liberal preferences. Sanders voted against the Iraq War and against repealing Glass-Steagall Act. And while he did vote for the 1994 crime bill, as Vox’s German Lopez has written, Sanders was equivocal even at the time, and in other instances in the 1990s spoke out against mass incarceration before it became as major of an issue within the party. On other issues such as free college, socialized health insurance, and income inequality, Sanders was ahead of much of his party.
So, while a younger rival could challenge Biden for representing old ideas, it’s much harder to throw that argument at Sanders, who could legitimately counter that he was fighting the party’s establishment on behalf of a radical liberal agenda well before it was popular.
This isn’t to say that age won’t become an issue for Sanders, or that he won’t face other serious challenges, such as his difficulty appealing to minority voters. It’s just that in the modern Democratic Party, unlike Sanders, Biden’s age becomes intertwined with the perception that his ideas and attitudes are from a different era.

