What this means is Democrat’s now control the investigation into President Trump. Democrats can also protect Special Counsel Mueller from being fired by trump . Trump is thanking God Democrat’s didn’t take the Senate because if they did the very first thing they would have done on January 19th when the new Congress is sworn in is impeach Trump. They can still impeach him with just control of the House but the Senate has to agree which probably won’t happen. It’s like what happened to bill clinton he got impeached by the house but the senate didn’t uphold it so he carried on as President