It seems as if the age of politicians has never been a hotter topic among Americans. Several polls show voters are weighing the president's age as a major factor in whether or not he could do the job for another term.
But if you ask former President Donald Trump, who is commanding the polls for the Republican presidential primary race, President Joe Biden is not too old to serve.
"Age is interesting because some people are very sharp, and some people do lose it, but you lose it at 40 and 50, also," Trump said during an interview with former Fox host Megyn Kelly. "But no, he's not too old at all. He's grossly incompetent."
At 77, Trump is just a few years younger than Biden -- the oldest sitting president in history -- who is turns 81 on November 20.
Trump also pushed back on polling data suggesting Americans think Biden is too old to be president. One poll found that 77% of Americans, including 89% of Republicans and 69% of Democrats, think Biden is too old to be effective for another four years.
That same poll found just over half of all adults think that Trump is also too old to effectively serve another term, including 71% of Democrats and 28% of Republicans.
"I feel I'm physically extremely good. I feel the same way I did 40 years ago. I feel as good as I've ever felt. Athletically, I'm just about as good as I ever was," the former president said.
Trump noted that many of his friends and world leaders are still sharp, even into their 90s.
"You look at some of the great world leaders, they were in their 80s. I mean, Churchill, so many people — they were phenomenal in their 80s," he said.
If Biden is re-elected, he would be 86 at the end of his second term.