If you’re referring to the Mueller investigation, I disagree. His investigation was very limited. There are a number of obvious questions that still need answering, from his banking issues to the question of whether he’s been compromised by Russia.
I'm referring to the 28 SEPARATE INVESTIGATIONS currently underway against Trump. This mythical 29th one, even if it's an impeachment, isn't going to uncover anything new.
But fine, if the Dems are bound and determined to go forward with impeachment without a majority in the Senate, then wait a few months. Time it so the impeachment is going on
on election day. Make people go to the polls while Trump is in the impeachment process. That's still risky (it runs the very real chance of turning the election into the referendum on the impeachment) but it mitigates the "Handing him a victor narrative" problem.
Also, and this is gonna be hard but it's important, no snide "Oh but you're okay impeaching Clinton for a blowjob!?" quips. Not one. Not from the Democratic Leadership, not from the network talking heads, not from the peanut gallery, not from the Democratic base, none. The Republicans are going to play the victim cards. They are going to say we aren't respecting the office. Ignore them. Shake it off.
Don't mention Clinton. If they mention him don't acknowledge it. Do not let this get turned into a narrative where this is just the Dems getting back for Clinton.
And as always if I'm wrong and they can get rid of Trump I'll eat all the crow anyone wants to serve me.