Harry Reid, a senator from Nevada for three decades and the Democratic Senate Majority Leader from 2007 to 2015, told me that Manchin underestimates the change in D.C. culture. “We’ve never had it like this before,” he said. “When Lyndon Johnson was Majority Leader for six years, he overcame two filibusters. In my first six years as Leader, I had to face and overcome more than a hundred filibusters. I think that you cannot expect the Senate to be a place where it’s kind of ‘Kumbaya,’ where you hold hands and sing.” But, when Manchin looks at today’s Republican Party, he sees, almost literally, his neighbors and friends. Since 2000, the congressional delegation of West Virginia has gone from all Democrats to all Republicans—except for him. The state has voted for a Republican in each of the past six Presidential elections, and in 2014 the state legislature flipped to Republican control for the first time since 1931. On January 6th, when word circulated on the Senate floor that Trump supporters had stormed the Capitol, Manchin did not initially assume the worst. “I’ve always been for a good protest,” he recalled. “My instinct was, Let them in! They’re raising all kinds of hell and hollering. Let them in! Let’s talk!” Soon, he glimpsed the horror of it—“Never in my wildest dreams did I imagine our form of government being attacked,” he said—and, during the impeachment trial, he voted to convict. But Manchin never broke faith with the Republican Party, and he was determined to work with it again. If politics is the art of the possible, Manchin’s likes and dislikes may determine what is possible for the Democrats—on police reform, gun safety, expansions of labor and L.G.B.T.Q. rights, and legalization of millions of undocumented immigrants—in the two crucial years before the midterm elections, when they risk losing control of Congress. Whether or not his peers like it, his unease with some key elements of the progressive agenda reflects the views of millions of Americans, not only people like him—what we might call Tommy Bahama Democrats, the prosperous boomers who look askance at Trump-supporting friends but have no plans to stop inviting them for dinner—but also rural voters who feel estranged from the Democratic Party. Manchin’s power is forcing Democrats to expand their focus on systemic inequities to encompass places like West Virginia, where substandard schools, high poverty, and distrust of government helped fuel radical conservatism. In that sense, Manchin’s innate conservatism also sets boundaries around the Party’s instincts, forestalling transformative changes that could drive away moderate voters in 2022 and 2024.