Authored by Garbiella Fine via RealClearPolitics.com,

The 2024 presidential campaign is now enmeshed in skepticism about Joe Biden’s mental acuity. Some 51 million Americans watched the president go one-on-one with Donald Trump in the June 27 presidential debate, which immediately ignited questions about the president’s age and the possibility of an open Democratic convention.

The oldest president in U.S. history, Biden will turn 82 shortly after Election Day, meaning if he wins the 2024 election, he would be 86 at the end of his second term. Today’s RealClearPolitics polling average shows that 78-year-old President Donald Trump has the lead in the national head-to-head contest by 3.4 percentage points. When RealClearPolitics White House correspondent Philip Wegmann asked Press Secretary Karine Jean-Pierre last Wednesday about Biden’s debate slip-ups and whether she’s noticed any slowdowns in the president, she responded, “He is as sharp as ever.” It seems that a significant majority of voters don’t believe this is true.

In a CBS News/YouGov poll published last Monday, voters were asked whether Biden should drop out of the race and allow another Democrat to vie for the title of the party’s nominee. Most voters (64%) believe it is time for a new Democratic candidate. Of the 1,130 registered voters surveyed, only 20% of respondents under 30 believed Biden exclusively had the appropriate cognitive health to serve as president. (The younger a voter was, the more likely they were to believe neither candidate had adequate mental fitness. 37% of voters under 30 felt that neither candidate had appropriate cognition, as did 35% of voters aged 30-44 and 28% of 45-64 year-olds.) The age group least concerned with the cognition of the 2024 major party candidates are voters 65 and up, of whom only 19% believed neither candidate had appropriate cognitive health.

While only 36% of voters believe Biden should continue to run, the older a respondent was, the more likely they were to believe that Biden should remain in the race.

Sixty-eight percent of voters under 30, 66% of voters aged 30-44, 64% of voters aged 45-64, and 58% of voters 65 and older believed it was time for a new nominee.

Look at the rest of the voter age categories, and confidence in Biden’s mental acuity drops.

The age category with the least confidence in Biden’s mental acuity alone was 45-64 year-olds (16%). Voters 65 and older were the most confident in Biden, with 26% responding that only the current president was fit to serve. Voters under 30 and aged 30-44 felt about the same, with 20% of the younger demographic and 19% of the older demographic believing exclusively in Biden’s mental fitness.

An older CBS News/YouGov poll of 2,159 U.S. adults conducted between Feb. 28 and March 1 shows that the 65 and older demographic most confident in Biden’s mental fitness seems not to have been affected by Biden’s debate performance. When asked the same question about the candidates’ mental and cognitive health, 25% were confident in Biden alone. Every other age group that answered “only Joe Biden” has declined. Adults under 30 had the most significant loss of confidence, declining 13%, and voters in the 30-44 and 45-64 age ranges declined 7%.

While all voters are troubled by the president’s apparent cognitive abilities, the oldest voting demographic is the least concerned.

Despite the slight boost from the oldest voters, most agree it’s time to give a new candidate the chance to beat Trump.

[ZH: The market odds of Biden getting the nomination are back at post-debate lows and Kamala Harris is now even…]

Explanations the White House has provided for Biden’s poor performance range from a bad cold and jet lag to Trump’s behavior, or just “a bad night.” Last Friday, Biden sat with ABC’s George Stephanopoulos in an interview the Biden campaign likely hoped would restore some confidence in the president’s ability to engage in straightforward, unscripted conversation. It did little to alter the conversation. While Biden seemed more alert than he did during the debate, only 8.5 million viewers saw the interview, nowhere near the number that viewed the debate.

[ZH: And last night’s gaffe-fest presser did nothing to help improve confidence in Biden’s cognition.]