The article below covers just one recent poll (NPR/PBS/Marist), and for better or worse it took place before the assassination attempt. While I don’t think this particular poll result is determinative, I do think it makes a lot of things that people think are determinative seem less, um, determinative.
The poll asked: Which is more concerning in a president, someone who doesn’t tell the truth, or someone who might be too old to serve? The results were lopsided: By 68 to 32 percent, respondents were more concerned about the lying than the aging. Given the relentless media focus on presidential age of late, that’s simply remarkable.
While the poll doesn’t directly compare Trump and Biden on that particular question, it also finds that 52 percent of Americans say Biden has the “character to serve as president,” whereas only 43 percent say this about Trump. Fifty-six percent say Trump lacks the character to serve, which surely reflects public perceptions of Trump’s dishonesty.