According to a new poll, the number of voters who think 78-year-old Donald Trump is healthy is declining and the number of those who think he is too old to run for president is rising.

Earlier, 81-year-old President Joe Biden dropped out of the race and was replaced at the top of the Democratic ticket by 59-year-old Vice President Kamala Harris. On Tuesday, Harris announced her running mate, Tim Walz, the 60-year-old governor of Minnesota, during a raucous rally in Philadelphia.

A new Morning Consult poll compared results from when Biden was still the presumptive nominee. When Trump ran against Biden, 58 percent believed the former president was in “good health” – that number has dropped to 52 percent now that he is campaigning against Harris.

More than half (51 percent) of respondents to the poll of 2,200 registered voters said Trump is now too old to run. By comparison, when he ran against Biden, only 44 percent said that.

Likewise, the share of voters who believe Trump is mentally fit for office fell from 53 to 48 percent with the change of his opponent – ​​a drop of five percentage points.

Trump is now the oldest U.S. presidential candidate ever and, if he wins a second term, would become the oldest sitting president ever – a title currently held by Biden. Biden has long been concerned about his age, but those worries were heightened after his disastrous performance at the June 27 debate.

Although Trump is only three years younger than Biden, he is not under the same level of scrutiny given his age, although he is similarly prone to slip-ups.

With Harris’ nomination, concerns about the candidates’ age have now shifted to the Republicans.

Seventy-one percent of voters said Harris was in good health, compared to 30 percent for Biden. Sixty-four percent said she was mentally fit, while only 35 percent said the same about Biden. Meanwhile, 48 percent said she was a strong leader, compared to 38 percent who said the same about Biden.

Only 12 percent of voters believe Harris is too old – while 70 percent said this about Biden.

Concerns about Trump’s age are likely to focus on his behavior rather than his fragility and longevity, as was the case with Biden.

About half of voters said they were concerned about Trump’s erratic behavior because of his age. Four in five of those who were unsure whether he would serve a second term were also unsure. About the same number are concerned about his ability to make decisions, and about two in five said they were worried that America’s strength abroad could be waning.

Harris has also increased her lead over Trump over Biden in terms of trust on several issues including abortion, the climate crisis, education, health care and protecting US democracy.

Trump’s lead has also shrunk on some issues, including gun policy, crime, the economy and foreign policy.

According to a poll conducted before Biden dropped out of the race, 36 percent of voters, including 45 percent of independents, thought it unlikely that Trump could serve a full four-year term if re-elected in November.