The impeachment process is primarily a political one. That is why Richard Nixon resigned before he was impeached (he was politically finished) and why Bill Clinton survived an impeachment trail (he had pretty good political support despite the impeachment, so Democratic Senators refused to convict).
So far, Donald Trump’s various scandals and even the Mueller report have not had a huge impact on his poll data. He has low support, but he still has had some support. But new data shows that in light of the recent Ukraine scandal, support for impeachment is growing among democrats (no surprise there), independents and republicans
That is very bad news for Trump.
It is made worse by the fact that Republicans face some very tough Congressional challenges coming up. There is a good chance that they will lose control of the Senate. The temptation for Republican Senators to dump Trump to save their hides will grow if Trump is impeached in the House.
Given (1) the severity of the illegal act, damaging the national interests rather than just evidencing personal moral and ethical problems, (2) the blatant way it was done and re-done, and (3) the widespread attempts to cover it all up, the pressure to vote for impeachment in the House is pretty strong. Keep in mind that Trump is impeached by simple majority vote in the House, and dems have a majority there. So is the vote now likely? Yes. Is it likely to succeed? Yes.
As I wrote above, it is less clear what will happen in the Senate. In order to convict on an impeachment, the impeachment articles much pass by a two thirds senate vote (67?). And in the senate, the Republicans have a slim majority. So conviction would require around 20 Republicans to break with their party and vote to convict. Will they? Who knows. Some might.
But even if Trump is acquitted, the vote in the senate comes after an impeachment trial. And Mitch McConnell has said that the trial cannot be blocked. It is going to happen. That trial is likely to impact Trump’s popularity as well as the popularity of the senators who are on stage. What about Trump facilitator, Mitch McConnell? Outspoken Trump man, Lindsey Graham? McConnell’s seat was usually safe, but may not be this race. Graham’s seat is still rated as safe. But who knows what will happen?
This will make the next half year a very interesting time for Washington politics.