Democrats are tethered to the President's low approval rating as the party faces darkening midterm prospects. Much like the Biden administration, the Democrats cannot escape voters' concerns over the economy and violent crime. It's clear why the president has avoided key swing states in advance of the midterms — he's a burden on his own party's electoral prospects.
While an incumbent president is always an electoral disadvantage, the GOP has thrown its rivals an electoral lifeline in the shape of extremist and under-qualified senate candidates. Republicans have put exceptionally poor candidates up for election in key states. Despite continuing ad hominem attacks on their political leader, polls have shown that voters often hold a relatively more favorable view of Democratic over Republican candidates.
There is a 15% chance that Joe Biden will no longer be US President before January 20, 2025, according to the Metaculus prediction community.