It's over 90 days until election day, the economy is improving and it's what it's like on election day that counts. The recent wins by the democrats will be kicking in by then too, improving things for tens of millions of Americans. Trump is yet to be spooked by indictments in Georgia and announce his run for 2020 (again) and how he was robbed. Meanwhile Mitch would blow Garland if he would indict Trump tomorrow and get him out of the way, they need to spin real hard this time around. A Trump TV trial in Georgia with 3 ring circus is not what Mitch or the GOP in Georgia need, but they might get it before the election, or at least indictments for Trump. However Georgia is only the first of many indictments for Donald, the hits will keep coming and Donald will keep freaking out. Once he's indicted the judge owns his ass and will muzzle him, so he's still useful running around like Chuckie with a knife inside the GOP.
Timing is everything and about all the democrats can realistically control, while staying inside the limits of the constitution and law.