He served as the show's anchor for 36 years before retiring in 2011.
During Thursday night's Democratic debate, people thirst-tweeted about the man, Luke Collis, sitting behind moderator Judy Woodruff.
The former vice president, 76, dismissed concerns over his series of campaign trail gaffes and jumbled statements.
"Maybe there does need to be a rematch."
"Imagine no longer needing to say this kind of stuff for your job but then saying it anyway," wrote one person on Twitter.
Donald Trump is going to be elected president. The American people voted for him a long time ago.
The television news business is a business (and so are newspapers). The idea here is to sell advertising, first and last. And advertising responds to big audiences. The bigger the audience, the more you can charge. That's all there is to it.
But I was stunned by the debate of Hillary Clinton and Bernie Sanders in Milwaukee, February 11, 2016. My surprise was not
Let the voters vote! Most of us aren't going to change our political positions or our voting decisions between now and November.
The debate was held at the University of Wisconsin-Milwaukee, in the Helen Bader Concert Hall at the Helen Zelazo Center