Can progressives remain in the Democratic Party?

If the progressive caucus is to remain in the Democratic Party, then will it be necessary to fight the status quo corruption in the Party as fiercely as it does the fascist Repugnacons? Is it really feasible to enact progressive legislation in tiny crumbs within the Party when our climate and human crises demands so much more? Can progressives play the necessary hardball politics to do so? 

So far I'm not seeing that they can. And if they don't then staying in the Party just provides them with lame excuses for not getting the job done for we the people. Learn to play hardball and do what's necessary. Taking over the Party is the only viable option, not getting along with it. If you can't do that then quit pretending. And maybe it's time for an actual progressive Party outside of the corruption.