He'll be acquitted, but it'll cost them the Senate. Even if he's convicted, it'll cost the the Senate. Pelosi did the timing on this very, very well.

It'll cost them the Senate in acquittal because it's clearly a sham trial that isn't a trial and more and more things keep coming out making Trump look worse and worse. Voters have noticed, 51% (overall, actual voters still below 50% but not far) want the Senate to remove him right now. With months still to go and revelation upon revelation of Trumps misdeeds continuing to pile up the backlash in the general will be considerable.

It'll cost them the Senate if they convict. "He got away with it for 3 years because of a compliant Senate" will be the dems overall theme. There will still be mountains of evidence of Trumps misdeeds accumulating and a compliant Senate enabling a corrupt pres is a fairly powerful message, the effects of which are multiplied by just how corrupt the prez was. Trump is in the "pretty fucking corrupt" column, so it's a big multiplier.