DAVID SHARP

PORTLAND, Maine - Maine Democrats delivered a rebuke to their party’s system of superdelegates on Saturday by adopting a proposal at their state convention to reduce the clout of unpledged elected officials and party insiders.

The adopted proposal strips power from superdelegates by requiring the state party chairman to account for their preferences and ensure the delegation sent to the national convention reflects the outcome of the state vote.

But it doesn’t take effect until 2020 for fear of running afoul of national party rules and causing Maine’s delegation to be penalized.

The proposal’s sponsor was inundated with messages from Democrats in other states seeking to follow Maine’s lead.

“That’s what happens when you have a good idea,” said state Rep. Diane Russell, of Portland. “It takes root, and it grows.”

Maine will send 30 delegates, including 17 pledged delegates for Vermont U.S. Sen. Bernie Sanders and eight for former U.S. first lady Hillary Clinton, to the Democratic National Convention in Philadelphia. The delegation also includes five superdelegates, at least three of whom support Clinton.

The proposal allows the state party to work around national rules giving autonomy to superdelegates, who are unpledged elected officials and party insiders, to ensure state delegations to the 2020 national convention reflect the will of rank-and-file voters.

During debate Saturday, Brigham McNaughton, a Democrat from Freeport, received a rowdy ovation when he described a “rigged system” in which superdelegates are allowed to defy the will of the voters.

“No one is super. We are all in this together,” added another speaker, Joanne Twomey, from Biddeford.

But Democrat Lynn Luzzi, of Knox County, said the current system of pledged delegates and superdelegates was created to avoid what happened in the Republican Party, allowing the rise of New York businessman Donald Trump, the party’s presumptive nominee. Republicans don’t utilize such a system.

Sanders won the Maine caucuses with 64 percent of the vote, and his supporters were a boisterous presence at the convention, booing and heckling former Rep. Barney Frank, of Massachusetts, when he urged all Sanders supporters to unite behind Clinton if she wins the party nomination.

Speaking on behalf of Sanders was fellow Vermont resident Jon Fishman, drummer from the jam band Phish, who encouraged supporters not to give up.

Supporters of Sanders are frustrated that superdelegates have given a boost to Clinton’s candidacy, and Maine Democratic Chairman Phil Bartlett supports a review of the outsized role superdelegates play in the nomination process.

“It’s important that we fully respect the vote of Maine people, and we should be pushing the Democratic National Committee to reevaluate the unpledged delegates,” he said.

Russell said her proposal was nonbinding for the current election to avoid violating national party rules. For 2016, it strongly recommends that superdelegates vote in proportion with the results of state caucuses won by Sanders in March but stops short of a mandate.

“I personally do not believe we should change the rules of the game in the middle of the election,” she said.

Bartlett plans to seek a meeting with Maine’s five superdelegates and report back on where they stand, party spokeswoman Katie Baker said.