Presidential historian Allan Lichtman believes the current polls showing Vice President Kamala Harris sliding against former President Donald Trump are “underestimating Democratic voting strength.” During a Wednesday YouTube livestream, the American University professor, who has predicted Harris would beat Trump in November, suggested that reports of Democrats pulling ahead in mail-in voting in certain states bode well for them. However, Democrats already made up the majority of mail-in voters, and Republicans have reportedly increased their relative shares in Pennsylvania, Georgia, Arizona, and North Carolina. “The polls in 2016 underestimated Republican voting strength,” Lichtman said. “It’s my view based on what...