Matt Rourke/AP
- Donald Trump boasted about his mental capacity, saying he "aced" a cognitive exam.
- The claim came after Trump confused Nikki Haley with Nancy Pelosi at a campaign event on Saturday.
- Haley, trailing Trump in GOP polls, then questioned Trump's mental fitness.
Former President Donald Trump is now boasting about his mental competency after he confused Nikki Haley and Nancy Pelosi during a recent campaign event.