Unfortunately, I doubt that the Ds will do much of anything.  They seem to still have this idea that the are the honorable ones and try to act as such.  The Rs have proven again and again that they will wage a scorched earth campaign to hurt the Ds, but the Ds don't ever really respond in kind.  In some ways, I prefer it that way, if both parties waged the same kind of scorched earth campaigns, it would destroy this country.  It is bad enough when 1 party does it.