The Democratic party has so far done an abysmal job at winning the favor of Bernie Sanders supporters this late in the primary. While Hillary Clinton seems more interested in winning over Conservative voters who are anti-Trump and starting “Republicans for Clinton” groups, key DNC coordinators are insulting the character of those who back the Senator and treating them like petulant children.

The Democratic convention’s chairman Ed Rendell discussed the upcoming July convention, making it clear whose side he was on.

“I think it’s gonna be a great convention, but of course the key to it is the Sanders people. Bernie’s gonna have his name placed in nomination; we’re gonna have a roll call; there’s gonna be a demonstration in support of Bernie; he’s gonna lose the roll call,” he said. “His supporters have to behave and not cause trouble. And I think they will, and I think Sen. Sanders will send them a strong message.”

Whether he is afraid of or annoyed with Sanders supporters, calling them out in such a condescending way is the one thing a DNC party member should not do in reference to Sanders’ anti-establishment supporters if they ever hope to win a single former-Sanders voter.

With the way the party is acting, it is no longer reasonable to expect Sanders supporters just to fall into party lines. They’ve got to earn progressive votes, and so far, they have completely failed.