They have passed a slew of bills to help that working class. See for example, a $15 hour minimum wage hike. All those bills have died in the Senate. However, they are trying their level best to have a center right democrat emerge. Biden seems to be the chosen one, but there are others in the wings (Harris, Mayor Pete, even Booker.)
If there is a perception that this was a Dédazo, a Mexican politics term I heard a lot south of the eight in 2016…people will stay home. Also, much of the middle class, mostly white progressive base of the party wants the president impeached even if there is no removal. Those are part of the small donor base, who are also very active in local Democratic clubs. Speaker Pelosi is trying hard to hold that tide, partly she learned the wrong lessons from the Clinton circus.