The hundreds of Bernie Sanders delegates who filled a hall at the Philadelphia Convention Center Monday applauded a speech from Sanders that largely echoed his campaign themes, but the crowd largely soured at the mention of Hillary Clinton. Bobby Cuza reports.

They may love Bernie Sanders, but that doesn’t mean they cheer his every word. Indeed, while the hundreds of Sanders delegates that filled a hall Monday at the Philadelphia Convention Center applauded a speech that largely echoed his campaign themes, the crowd largely soured at the mention of Hillary Clinton.

Sanders tried to settle the crowd and wave off the chorus of boos, saying this is the real world we live in and describing Trump as a bully and a demagogue.

“Trump is a danger for the future of our country and must be defeated. I intend to do everything I can to see that he is defeated," said Sanders.

Sanders praised the resignation of Debbie Wasserman Schultz for opening up the possibility of new leadership at the DNC, but it’s not enough for many of his delegates here, who also list among their grievances the choice of Tim Kaine as Clinton's running mate.

“There is serious interest right now and exploration as we speak in a formal challenge with an alternative candidate to Tim Kaine," said Norman Solomon, Bernie Delegates Network.

At a briefing Monday morning, representatives of the Bernie Delegates Network also raised the possibility of protests on the convention floor; not to mention the thousands of Sanders supporters who took to the streets. Many acknowledge party disunity could ultimately help Trump win, but they say Clinton and the DNC would have only themselves to blame.

“If this is a family, we have a sister who’s been lying and cheating, and this would be a dysfunctional family if we allowed that to go on unchecked," said Gabrielle Dolphin, Sanders delegate.

“If she wants the party unity – everybody clap your hands and jump and sing – that’s not going to come easy with us," said Manuel Zapata, Sanders delegate.

As for who might be nominated in Kaine’s place, Sanders delegates say that’s a work in progress.