However, despite that unsuccessful outcome, the Dems must try. Why? Because of his oath of office:
"I do solemnly swear (or affirm) that I will faithfully execute the Office of President of the United States, and will to the best of my Ability, preserve, protect and defend the Constitution of the United States"and their's:
"I, AB, do solemnly swear (or affirm) that I will support and defend the Constitution of the United States against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same; that I take this obligation freely, without any mental reservation or purpose of evasion, and that I will well and faithfully discharge the duties of the office on which I am about to enter. So help me God.”
While Trump has not been faithfully executing since the day he started (emoulements), the key now is that he and his staff are refusing to comply with subpoenas. I have been thinking about this being the breaking point for some time, and then someone on twitter (sorry, I forget who) reminded me that there are two oaths here. That the members of the House of Representatives didn't swear to do their job when the polls favor it or when success is likely. They swore to support and defend the Constitution. When the President clearly is not faithfully executing the Office and denying Congress's proper role as overseer of the executive, then it is time to act.
It is simply the right thing to do. It is what they are obligated to do, focus groups or polls be damned. Not doing so sends a strong signal that Trump can continue to abuse his powers with impunity. While failing to convict in the Senate would send a similar message of impunity, the process would be painful for Trump, his team, and for those Senators who vote to protect him. It is time to put them all on the spot, the hot spotlight. Trump will react poorly, of course. He will have his temper tantrums AND people might just learn what is in the Mueller Report. It might just change public opinion as the impeachment process did in 1974. Of course, the difference this time is that Fox News exists and exists to protect the President. In 1974, there were three network news programs, and they played it straight. This time, not so much. So, I doubt that many Republicans will be swayed by the process, but some will. As will some "independents."
The key again is this: calculations are fine and dandy in normal times. But right now, we have a President and an Attorney General who believe the President is above the law. It is time to teach him that this simply is not true.