A huge issue facing the Democratic party is that, like yourself with Palestine, many of their voters care deeply and passionately about a singular issue, to the point that it is their North Star politically. On a human level, there is absolutely nothing wrong with this, to be clear, and in theory political parties should be an amalgamation of "north stars" broadly united towards a common goal.
Where we run into problems is that in the current state of America, the North Star political issue to 95% of Republicans is "own the libs." That's it. When winning is the ultimate shared goal, it makes it much easier for folks from different walks of life to come together and get behind ideas that might not fully align with their core belief system.
If they want to stop the onslaught of the country by the current party in power, Democrats will either 1) need to focus on aligning the entire coalition behind "winning" as the primary goal or 2) somehow break the "own the libs" trance that Fox News has on Republican voters.
I know which one I think is easier to achieve.