Mark Whittington has a largely reasonable assessment of the implications of the Democrat takeover for space activities. I'd just add (though it's not really associated with the takeover per se) that one other interesting potential change in the new Congress would be the return of Jim Sensenbrenner to the House Science Committee, as ranking member (he would have presumably gone for the chairmanship if the Republicans had retained control). As noted in comments at the link, he will be much more skeptical of NASA, and welcoming of commercial activities, than many of his predecessors.