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While Nancy Pelosi was meeting with a group of columnists yesterday, she pointed to a portrait of Abraham Lincoln hanging on a wall of her conference room and paraphrased a famous line of his that has long been a favorite of hers.

“Public sentiment is everything,” she told us. “With it, you can accomplish almost anything. Without it, you can accomplish virtually nothing.”

Public sentiment is going to determine the outcome of the impeachment inquiry. If Democrats can persuade even a small share of President Trump’s supporters that he shouldn’t be president, he will almost certainly lose the 2020 election. If Democrats can persuade a modest share of those supporters, he will be at risk of losing the support of congressional Republicans and being removed from office by the Senate.