Biden says his 'mental acuity has been pretty damn good' in defending his decision to stay in the race

After having tempered attacks on Donald Trump following Saturday’s assassination attempt, President Joe Biden plunged back into campaign mode Monday, defending his decision to remain in the presidential race despite calls for him to exit.

In an interview with NBC News anchor Lester Holt, Biden at times grew combative and said he isn't leaving the race even though some Democratic leaders have expressed fears that he can't win.