Republishing the post below from December 2016. TLDR version - old political warhorses like Biden do well in party primaries and less well in general elections. Doesn't mean he can't win though, just that it's harder. (And note the wrong idea I had that Biden couldn't possibly run in 2020.)
I don't think it applies to Sanders because except for the last few years, he didn't do much to help Democrats beat Republicans. Not sure that really works in his favor, though.
Biden does seem to have a demeanor that makes him "moderate" rather than "compromised" so that might help him, but we'll see what a primary and general campaign does to that image.
And while I'm saying this is how American politics work, I'm not saying I'm happy about it. It's crazy that Pete Buttigieg has a better chance now than 20 years from now when he's been forced to make hard decisions and compromises. But it's what we've got.
The old post from December 2016:
People may be sick of political introspection, but for those who can
handle a little more, here's a list of old warhorse nominees:
H. Clinton
Gore
Dole
Bush Sr.
Mondale
Plausible additions, although not a perfect fit:
Romney
McCain
These are people that had been prominent for a long time and had done a
lot of favors inside their party, so they had built alliances within the
elites and started their campaigns with a fair amount of name
recognition within their parties. They also didn't do very well in
winning the Electoral College. Bush Sr is the only partial exception,
going 1-for-2.
I suppose Reagan could be argued as a counter-example, but he wasn't
very cozy with Republican elites in 1980, and that's also going back a
ways in political history. Even if you did include him, the warhorse
win-loss record is pretty bad.
Our political system, for worse rather than for better, values newness
and "authenticity" over experience, compromises and baggage. I'm open to
suggestions as to how that can change, but I'm not up for beating my
head against the wall. The warhorses don't make good general election
candidates, and Democrats shouldn't choose them in upcoming elections.
And good news, the only warhorses Ds have lying around these days are
former nominees and Biden, none of them likely to run again. But the
problem will return someday.
Second and related issue is prominent Democrats becoming lightning rods
for Republican lies. Hillary was their target with the willing
assistance of the New York Times and some other media. The result made
her the second-most unpopular nominee in history.
Hillary wasn't the sole target of hate and lies - before her, it was
Gore. While I hate to let the Republicans win their little game, maybe
it's time for a little political judo - the Republicans are spending
all their lies on warhorses they see as future nominees, and those
people aren't the best nominees anyway. So don't nominate the lightning
rods that Republicans have been lying about, and use 2008 as a model.
The Republicans had no coherent critique of Democrats, let alone a
message of their own, and just had Hatred for Hillary. That let Obama
define a completely different, hopeful, and moderately progressive
alternative.
We'll see what the Republican game plan will be for 2020 - something
tells me that it won't be a positive message based on a record of
accomplishments. They also won't have 2008's McCain who tamped down on a
new set of lies against Obama.
I'm not saying run from any candidate the Republicans start lying about, just to choose wisely instead.