Democrats often let out a sigh of relief at inappropriate times. That's one of the reasons they were so angry when Hillary lost. Democrats are barely half way through the nominating process so it ain't nearly over. Be careful what you wish for democrats. Bernie is still viable and sleepy Joe is still brain damaged.
That's why they're so desperate to shut down the primaries. They know that, like Hillary, the more exposure Biden gets, the less support he'll see.