 The main concern, or one of the main concerns we've seen over and over when it comes to Biden, and that is his age. This is a Gallup poll just before the debate, and already going into the debate, 67% of voters said they considered Biden too old to be president. That's 30 points higher than the number for Donald Trump. And just take a look at the other oldest nominees in history. John McCain in 2008, Dole in 1996, Reagan in both of his campaigns.