President Joe Biden has been in Las Vegas this week for a whirlwind campaign tour intended to counter his opponent’s messaging at the Republican National Convention in Milwaukee.

To emphasize his commitment to combating the drivers of inflation and economic hardship, Biden on Tuesday unveiled a plan to cap rent increases at 5% for large landlords.

But on Tuesday afternoon, during remarks to the NAACP’s national convention, Biden got one of the basic features of the plan wrong.

“Look, folks, the idea that corporate-owned housing is able to raise your rent three, four hundred bucks a month — well, I’m about to announce, they can’t raise it more than $55,” he said.

Biden paused for a second before saying $55, suggesting he was searching for the right number. (The plan would cap increases at 5%, not a specific dollar amount.)

In response to an inquiry from HuffPost, the Biden campaign did not directly address his misstatement or how it might affect efforts to demonstrate his mental agility in a contest with Trump.

“Yesterday, President Biden showed his commitment to bringing the country together as he laid out his vision to stand up for civil rights, grow an economy where hard work pays off, and make housing more affordable,” Biden campaign spokesperson Sarafina Chitika said in a statement.

“Meanwhile at the RNC, Donald Trump and his MAGA allies doubled down on extremism, division, and their Project 2025 agenda, making it clear that they are only interested in helping billionaires while turning Americans against each other. The choice couldn’t be more clear.”

Biden cited the correct number later in his remarks. But on three occasions, he also lost his train of thought, finishing an incomplete sentence with the word “anyway” — a tactic he has been employing frequently of late.

“We’re going to bring rents down. As I said, we’re going to build 2 million affordable homes and cap rent increases at 5% a year so corporate landlords can’t [inaudible] — anyway, I don’t want to get going,” he said. “I’m going to get very upset.”

The gaffe — and other awkward moments in the speech — add to questions about Biden’s communication skills at a time when many elected Democrats doubt his ability to defeat Trump in November.

Trump, who is 78, is known to have verbal slip-ups of his own, but in a debate watched by over 50 million Americans on television, he was in greater command of his thoughts and words. While less than one-quarter of American voters believe Biden is “mentally sharp,” nearly six in 10 believe Trump is, according to an early July poll conducted by Pew Research Center.

Biden, 81, has been defiant in the face of calls to withdraw from the race following a disastrous debate performance on June 27. The themes of his Las Vegas speech were a case in point, focusing on his plans for the first 100 days of his second term.

In front of a loyal, cheering audience of Black Democrats and elected officials, Biden occasionally nodded to the criticism he has received in the press and some Democratic lawmakers. He quoted former President Harry Truman’s famous line: “If you want a friend in Washington, get a dog.”

“Guess what? After the last couple weeks, I know what he means,” Biden said, drawing laughs from the crowd.

But Biden is not out of the woods yet. Even as congressional Democrats’ calls for Biden’s withdrawal have slowed following the attempted assassination of Trump on Saturday, dissent has persisted in other forms. Several congressional Democrats objected to the Democratic National Committee’s plans to hold a roll call vote formally confirming Biden as the nominee as early as next week. In response, the DNC announced Wednesday that the nomination process would not proceed until the first week of August.