Former President Donald Trump mistakenly referred to Barack Obama instead of Joe Biden at a Virginia rally, in a statement about Vladimir Putin and nuclear weapons. This was the third such confusion in six months, raising concerns about the cognitive fitness of Trump. The Republican frontrunner, who is 77, and Biden, who is 81, are the oldest individuals to run for U.S. president. This gaffe follows Trump's prior mix-up of Nikki Haley and Nancy Pelosi and mirrors Biden's own recent slips, such as confusing Ukraine and Gaza. A New York Times/Siena College poll indicated that 73% of voters are concerned about Biden's age affecting his presidential effectiveness.