(CNN) Democrats charged with reworking the "superdelegate" system took a big step Wednesday to change the way candidates will win the party's nomination for president.

The Rules and Bylaws Committee of the Democratic National Committee met by telephone and voted in principle on a measure that would severely limit the influence superdelegates have on the nominating process, ensuring candidates earn the nomination through delegates won through primaries and caucuses.

Under the proposal, superdelegates, who are typically party leaders and officials, would not be able to vote on the first ballot for the presidential nominee at the DNC's convention unless a candidate has already earned enough pledged delegates to win the nod outright without superdelegates. The measure prevents superdelegates from delivering a victory to a candidate on the first ballot who hasn't won enough delegates during the primary process.

The DNC secretary would certify the primary and caucus results after the final state contests to determine if superdelegates would be eligible for a first ballot vote.

The changes stem from the deep lack of trust Sen. Bernie Sanders' supporters had for superdelegates during his 2016 run for president against former Secretary of State Hillary Clinton. The early support of superdelegates was viewed by Sanders' supporters as having tipped the scale for Clinton.

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