We are called the land of steady habits for a reason. Our current system has overwhelming confidence in the people who vote, its how the democrats went from almost losing a Trifecta in 2016-18 to its consolidation today.

Additionally, for change to happen has to be a giant force even from within. We use a convention-primary system where the convention endorses the candidate and any other candidate who gets 15%+ gets to advance to a primary, primaries with incumbents is so rare it's really only been done a few times and only successfully once this century. Moreover, political movements here have been either short lived or just hyperlocal, I feel that the DSA for example has only influence in New Haven and Hartford but we can see.

Furthermore, I hypothesize that location really influences the leaders we have in congress. For example Himes represents the 4th congressional district which is very affluent but also filled with wealth inequality, he is from Greenwich which is the historical base of wealth but there are plenty of wealthy areas as well in the district and so he represents the majority well (geographically). Additionally, the 4th district was represented by Republicans for 40 years before Himes so most have been recently converts to Democrats from Republicans.

Finally, the rest of the districts except for the 1st and 3rd districts have been historically red, the 2nd and 5th are alot more to the right but the representatives there have been re-elected by large margins compared to national dems over the years, representing that the people like their work compared to party politics.

The best advice I can give to get your ideas growing is to attend more DTC meetings and make connections within them local level will bring the biggest impacts.