From a Wall Street Journal story by Josh Zumbrun headlined “For Biden and Trump, Age Is Really Just a Number”:

Either Donald Trump or Joe Biden would be the oldest person to win the presidency if they prevail in next year’s election. At age 77 and 80, respectively, both are already past the U.S. life expectancy of 76.4 years.

It’s become a major source of voter concern and media attention. In a CBS News poll, only 34% of respondents thought Biden would complete a second term and only 55% thought Trump would.