President Trump has basically been daring the House Democrats to impeach him and send the proceedings to the Senate for a trial:

It’s entirely possible that Trump isn’t just saying those things out of frustration, but rather because he’s been made aware of how all this is playing out against the Democrats:

If this is accurate it’s no wonder Trump is demanding the Democrats proceed with impeachment:

Keep on digging, Dems!

Apparently the Democrats think they’ve come too far to stop now, even if it backfires badly.