After the seventy-third ballot had been called, to no effect, at the Democratic National Convention on July 5, 1924, in the old Madison Square Garden, a delegate from Oklahoma named A. H. Ferguson rose with an idea for breaking the deadlock. According to the Times, Ferguson thought that “the whole trouble was that the convention was being held in New York, a wicked city.” He proposed packing up and moving the gathering elsewhere. There was some sympathy for that plan among delegates who found New York expensive, if not wicked, and were struggling to pay their hotel bills as the Convention stretched into a second week. But Ferguson’s suggested alternative, Kansas City, was greeted with derision and shouted proposals of Washington or Indianapolis—or Cleveland, where the Republicans had met earlier that summer. This was indicative of the Democrats’ larger problem, the Times reported: “Everybody was against somebody or some place, but not enough people were for anybody or any place.”

The Republicans will meet in Cleveland this July, too, for what many in the Party are openly hoping will be a contested Convention, if only because the most likely alternative is Donald Trump winning the nomination outright. So far, as in 1924, not enough people are for anybody else. But Mitt Romney has called on Republicans to vote strategically in the primaries, in order to deny Trump the majority of the twelve hundred and thirty-seven delegates he needs. John Kasich has said that a brokered Convention would be “exciting” and his path to victory. And Ted Cruz, who has won the second-largest number of states and delegates, is not the type to quietly step aside.

The last contested Republican and Democratic Conventions were in 1948 and 1952, respectively, and both nominated a candidate on the third ballot. The 1924 Convention went to the hundred-and-third ballot, before rejecting both front-runners, former Treasury Secretary William McAdoo, of California, and Governor Al Smith, of New York. It has lately drawn attention as an extreme example of what Politico has called “conventional chaos.” What tore the Convention apart, however, wasn’t choosing a nominee, or even Prohibition, divisive as the fight between the drys and the wets (many of them wicked New Yorkers) had been. It was another question, one that Trump’s candidacy has brought back to the fore: whether, and how strongly, to disavow the Ku Klux Klan.

McAdoo, who was married to President Woodrow Wilson’s daughter, had positioned himself as the enemy of New York and of Wall Street, even though, as a lawyer and a businessman, he had made a good deal of money there. (Apparently, he hadn’t made enough: during the campaign, it emerged that he’d been on a twenty-five-thousand-dollar retainer from an oil man implicated in the Teapot Dome scandal.) As Robert Murray notes in “The 103rd Ballot,” the standard history of the Convention, the Klan was then in the midst of a major revival, and McAdoo wanted its support.

But Senator Oscar Underwood, an anti-Klan Alabamian, pushed to include a plank in the Party platform condemning the group, declaring that “it is just a question of being brave and facing the issue squarely.” Smith, a Catholic despised by the Klan, favored Underwood’s plank. McAdoo deployed his supporters to defeat it in a late-night floor fight that included actual wrestling and punching. It was defeated by a handful of votes. Afterward, thousands of Klansmen paraded in New Jersey, where one speaker called New York a “foreign country.”

McAdoo managed to kill the plank, but he also killed his candidacy. There were now enough delegates who framed their opposition to him as a matter of principle. Smith didn’t have enough votes, either, and the balloting played out over several bitter days. The Times, describing the “hollow-eyed” delegates, concluded that “if this convention had been a fight it would long ago have been stopped by the referee on the ground of humanity.”

One of the few figures who remained calm and smiling almost to the end was Smith’s floor manager, Franklin D. Roosevelt, who was making his return to the political stage after contracting polio. Midway through the balloting, Newton Baker, a former Secretary of War, asked Roosevelt what he made of it all. “Well, Newt, the first hundred ballots are the hardest,” Roosevelt said. Finally, Smith offered to withdraw if McAdoo did, and McAdoo released his delegates. They drifted to John Davis, a former West Virginia congressman who had been in seventh place on the first ballot, with just thirty-one votes.

Davis lost the general election to Calvin Coolidge, in a landslide. And yet the 1924 Convention could have been worse for the Democrats. What if McAdoo, with his opportunistic turn to nativism, had won the nomination, having cemented the Klan’s institutional place in the Party? What would the political alternatives to Hooverism have looked like when the Depression awakened the country’s deepest fears? The proceedings at Madison Square Garden were broadcast live on the radio, and, in some parts of America, as Murray writes, there was shock at the “urban rowdyism” of Smith’s supporters. “ ‘Boos and booze’ ought to be the Smith slogan,” a Tennessee delegate said. Yet there is comfort in knowing that Klan sympathizers were pelted with Bronx cheers. You might call that New York values. It was decades before the Democratic Party got itself out of the depths on race, but an objection had been registered.

This summer, in Cleveland, the Republican Party may be faced with tests that not only are tactical but go to its identity. Most delegates are bound only for the first and second ballots, so in a contested convention the choices of individuals matter, too. The Republican National Committee’s rulemakers will meet a week before the Convention, and, though they don’t have absolute discretion—the delegates must approve key rule changes—they may try to make winning harder for Trump. There are risks in that, given that many of Trump’s supporters already believe that the system is rigged. The G.O.P. may have to decide what scares it more: losing without Trump or winning with him.

That decision may just be a matter, to borrow Underwood’s words, of facing Trumpism bravely and squarely. Or it could all go on for a while, in which case the G.O.P. might also have some use for Roosevelt’s reminder: the first hundred ballots are the hardest. ♦