Tom Perez, chairman of the Democratic National Committee, and Senator Bernie Sanders. Photo: George Frey/Getty Images

Democrats voted overwhelmingly on Saturday for the biggest reforms to its presidential nomination process in decades, including a major reduction in the power of superdelegates, and a measure to make state caucuses more accessible. The reforms were approved after a four-hour debate at the Democratic National Committee’s meeting in Chicago, and were backed by both DNC chairman Tom Perez and Senator Bernie Sanders, who had sharply criticized the role of superdelegates as he ran for president in 2016.

Under the old process, superdelegates — made up of members of the Democratic National Committee, elected officials, and distinguished party elders — were not bound to the outcomes of primaries and caucuses, but could vote to nominate whichever presidential candidate they wanted at the national convention. This gave them an outsize, and in the minds of many, unfair role in determining the party’s nominee. (Superdelegates made up about 15 percent of the delegates at the 2016 convention.)

Under the new process starting in 2020, superdelegates will still be able to attend party conventions as delegates, but will not be able to vote in the first round of ballots and will be able to vote in the very rare event of a deadlock.

The way state caucuses are governed will also change under the reforms, with state parties now required to accept absentee votes, rather than requiring caucuses voters to be physically present to support candidates at the events. That fundamentally changes the nature of caucuses, which are old-school, state party-run affairs that force campaigns to not only engage and win over supporters, but get them to show up in person and remain organized amid the chaos. Barack Obama’s underdog victory against Hillary Clinton in 2008, for instance, relied on his campaign’s strategy of dominating the state caucuses. And had Obama not won the first caucus in Iowa, he might have never gotten enough momentum to win the nomination.

Caucuses are also run by the state parties, as opposed to primaries, which are run by the states themselves. Saturday’s changes are expected to accelerate more caucus states switching to primaries — another change sought by reformers.

The new rules are a big victory for Sanders, who lost the party’s contentious nomination battle to Hillary Clinton in 2016, but thanks to his newfound popularity and passionate base, now exerts considerable influence over the direction of the party. Clinton won the majority of delegates based on the primary and caucus votes in 2016, but was also the predominant choice of the party elite who made up the superdelegate pool, something the anti-establishment Sanders and his supporters saw as an unfair advantage at a time they had already been accusing the DNC of showing favoritism toward Clinton.

“Today’s decision by the DNC is an important step forward in making the Democratic Party more open, democratic and responsive to the input of ordinary Americans,” Sanders said in a statement after the vote.

The changes marked the culmination of a two-year-long process that began as a way to soothe the intraparty animosity of 2016, and was led by the Unity Reform Commission, a group that was joint-established by the Sanders and Clinton camps at the convention that year. The commission had agreed on the necessary changes in December, and eventually passed along their recommendations to the DNC’s rules and bylaws committee

But opponents of the reforms continued to make their case ahead of the vote, making for a tense and emotional meeting at times.

Superdelegates were created to be the last line of defense against outsider, potentially disastrous candidates, and everyone has now seen a real world example of what can happen if someone like Donald Trump can win a major party’s nomination and its de facto leader. Critics point out that the new rules may make it easier for such candidates to win the right to represent the party regardless of what the party establishment — or the party’s activists — ultimately thinks of them:

Sanders & his team are super dumb - all these reforms make it more likely Democrats get a media savvy moderate nominee like Avanetti. More open primaries, easier access to caucuses, slightly less superdelegate influence. Big blow to the left. — Kenton (@KentonTilford) August 25, 2018

There was also pushback from older black delegates, who argued that the reforms would reduce the power and influence of hundreds of black and Latino party leaders, and result in less diversity on the convention floor — a possibility reformers dismissed, citing delegate diversity requirements. When former DNC chair Don Fowler, who helped organize opposition to the reforms, said at the meeting that the moves would “disenfranchise” minority groups within the party, some people in the crowd at the meeting tried to shout him down, calling him a liar.

Another former DNC chair, Howard Dean, wholeheartedly endorsed the changes in a video played at the meeting. He argued that the DNC should respect the will of grassroots voters, and that young voters “have lost faith in our party’s nominating process, and make no mistake, this is a perception that’s cost us at the ballot box.”

Trusting the Democratic party’s electorate over its elites was a common theme among the reformers’ pitches in Chicago. “Voters want us to be listening to them, and this is a way to show that we’re listening, to show that we’re understanding the changes that had to be made after 2016,” DNC vice- chairman Michael Blake said on Friday. Perez and others also emphasized before the vote on Saturday that Democrats’ most important common goal was electing a Democrat to the White House. Attracting new and younger Democrats, avoiding intraparty conflict, and respecting voter’s wishes would, Perez insisted, put the next Democratic nominee “in the strongest position possible” to win back the White House.