In one of them, MoveOn.org activists are targeting undecided and committed Hillary Clinton superdelegates with a clear message: wait until all the votes are counted before throwing support behind a candidate.

The effort, which will begin this week after MoveOn.org polls its supporters to pick which superdelegates to petition first, comes amid growing criticism from Sanders supporters who complain that the game is rigged in the former secretary of state’s favor.

As of Sunday, the petition had 112,107 signatures with a goal of 125,000 signatures.

“The next big thing will be this wave of petitions targeting individual superdelegates,” said MoveOn Washington Director Ben Wikler. “Asking individual members of Congress and governors and other superdelegates to individually make a pledge to support the will of the voters when it comes time to count their votes.”