If Democrats can't stick together to defeat a fairly unpopular bankruptcy bill, or a trade agreement that not that many people outside of the beltway feel much love for, I doubt they could find the votes to impeach in the House, even if they had majority after November.
Thus far it seems that the voices calling for impeachment are the extremists in the Democratic party. In fact, many of the people calling for impeachment could be said to be ultra-left wing "ideologues".