The last thing in the world the Democrats want is a GOP senate.
While true there isnt a whole lot of difference between a Dem Senate and a Repelicans senate when they are both run by the progressives in their party and they both hate conservatives.
Last time the Repelicans had the senate they gave half of the committees to the Dems and didnt slow down spending and dime while approved a bunch of Government expansions for the dependency class.
That was like a barely half held Senate. Get comfortably over and the tone would change.