As has been discussed, there is no “Shadow Govt” in the USA, but in a two-party system, the Dems are clearly “the opposition.” That said, as we have found with Republicans and MAGA, there are “wings” of the parties and they don’t always see eye to eye on how to govern or live in opposition.
This is where the Dems have had bigger problems than the Reps, as it has been clear that the Reps have needed to fall in line behind MAGA to get elected or stay elected, whereas the Left Wing of the Dems feels like they’re the future (young, feisty, often driven by students, and believing they represent the future of the country) and being held back by the entrenched old guard that have backed Hillary, then Biden, then anointed Harris. It’s why, in many respects, there seems to be no reasonable opposition to the shock and awe Trump is creating in Washington. However, it is Trump army of far right operatives operating in the shadows, whom he is allowing to completely reshape the country while he tries to be king, that are the force behind the throne. This “Holy Alliance” of Christian Nationalists, who even managed to get JD Vance as their VP and future President-elect as part of the bargain, who are running domestic cover for Trump while he blows up every convention in place meant to stop it from happening!
Against THAT threat, there is no serious Democrat response, and the country is literally relying on “the Courts” to hold the position as an “equal co-branch of government.” Trump has already tried to dominate that arena with appointments to the life time Federal Bench, but there are still judges who are willing to stand up to him, which is LITERALLY saving us from being a Dictatorship TODAY…and, sadly, the ONLY THING STOPPING HIM, as the law is the only brake against him extracting all the power!