The Democratic National Committee (DNC) has just voted to enact the most consequential reforms to the party’s nominating process since the 1980s. The more than 400 voting members of the DNC overwhelmingly passed a reform package curbing the influence of superdelegates by a voice vote of acclamation. The reform package also included a host of lower-profile changes.

The DNC created its superdelegate system in the 1980’s. Unlike pledged delegates, superdelegates are free to support a candidate of their choosing at the presidential nominating convention, regardless of how voters cast ballots in their state. Superdelegates represent 15 percent of the overall delegate count and are the party’s most high-profile members.

Controversy over the superdelegate system erupted during the 2016 primaries, when vast majority of superdelegates sided with Hillary Clinton over Sanders early in the nominating process. Sanders supporters claimed that Clinton’s early support from superdelegates unfairly tilted the race in her favor and called for the superdelegate system to be abolished. The issue has been under debate ever since.

Under the new reform package, superdelegates will no longer be allowed to vote on the first ballot at a presidential nominating convention. For the initial vote, candidates will only be able to count the delegates they won during state primaries and caucuses. If there is need for a second ballot, then superdelegates will be called on to vote. Superdelegates can vote on the first ballot if a candidate already has such a large delegate advantage from caucus and primary wins that they would win the nomination without superdelegate support. Superdelegates can still endorse and advocate for candidates.

DNC Chairman Tom Perez says the reforms will address the “perception” of unfairness in the presidential nominating process. DNC members also voted to approve the creation of a new Ombudsman Committee, place stronger safeguards on DNC members’ conflicts of interest, and provide greater oversight of the party body’s finances.