(NewsNation) — Americans are concerned about President Joe Biden’s health and mental fitness as he hits the road for his reelection campaign.

A new NBC poll shows 68% of respondents have “some concerns” about Biden’s mental fitness, and 55% have “major concerns.”

On the other hand, fewer people have the same concerns about former President Donald Trump, with 55% saying they have “some concerns” about Trump’s mental fitness and 44% saying they have “major concerns.”

The same poll also found two in three Americans believe the country is headed in the wrong direction, a fact that doesn’t bode well for an incumbent president.

Though not by much, Biden continues to lead Trump in most polls, and his favorables are slightly better than Trump’s.

Still, the president’s approval ratings sit in the low to mid-40s.

Also running in the Democratic pool is Robert F. Kennedy Jr. Polls suggest Democrats aren’t exactly jumping on the RFK Jr. train yet, but his success among some Democrats and independent voters could prove to be an issue for Biden.

Meanwhile, Kennedy is going viral after posting shirtless workout videos, seemingly intended to highlight his own physical and mental health as contrasting that of President Biden’s.

Last week, Kennedy challenged Biden to a debate, which he declined. It is currently unclear whether Biden will ever agree to debate him. So far the Biden campaign has largely ignored Kennedy.

As Biden hits the campaign trail, he will be forced to contend with concerns about his age and questions about the economy from voters.