I'm not sure winning in the midterms will be a net positive for Democrats (barring an infeasible supermajority). Even if they stop everything Republicans want to do (which they won't even get close to), that's just going to become the excuse for the next Republican campaign to blame Democrats for a dysfunctional government, and there's a good chance Democrats would lose as a result. I wouldn't be surprised if it would actually turn out better for Democrats if they stay a minority so that they can't get the blame during the presidential election.
Winning the midterms would make the house speaker a democrat, which would allow for the removal of both the president and vice president via impeachment such that the democratic speaker of the house becomes the acting president, effectively stopping the bullshit of this administration. The question then becomes if the amount of flipped senate seats + the number of republican senators voting yes on impeachment reaches a supermajority. Possible for Trump, highly unlikely for Vance. This was likely the angle Republicans plan to take, as that would make Vance the Incumbent in the 2028 elections, giving him a statistical edge. It also allows for the current republicans in office to look like they are trying to meet the demands of their constituents without giving up any real power and effectively not changing their agenda. A reminder that although Trump is a rapist, the fight against this administration will not end with him. Republicans will continue to employ smoke and mirrors strategies and lean heavily into value extraction from the US and global economy as has been occuring.
Republicans have been a buttplug in the political process for going on twenty years, and yet who has the majority in congress?