I’d love to see Donald Trump beaten in 2020, and it should be easy enough. His list of accomplishments is short, most Americans express strong disapproval of his behavior, and he has done little to win over people who don’t already support him. Yet he stands a good chance of re-election. One in five registered voters is up for grabs in 2020, according to a Washington Post-ABC News poll, while Mr. Trump’s approval rating among independents has risen from 35% to 42% since June, according to an NPR/PBS NewsHour/Marist poll. What gives?

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