The impeachment talk isn't going anywhere in 2019, folks. Tom Steyer, the billionaire Democratic mega-donor, has decided not to run for president because he thinks pursuing Donald Trump's impeachment is a better use of his vast fortune. There is a strong appetite for impeachment among the liberal grassroots as well. But impeaching a president, to say nothing of removing him from office, is complicated and, I think, ultimately unlikely in Trump's case, not least because House Speaker Nancy Pelosi has insisted it's not worth pursuing.

Here, in reverse order of likelihood, are five possible impeachment-related scenarios that could play out between now and 2020.

Scenario 1: The House votes to impeach Trump and he is removed from office by the Senate.

You've got to be kidding, right? The 1-11 University of Connecticut Huskies have a better chance of beating Clemson in next year's college football national championship than Trump has of being removed from office by his own party in the Senate. Mitch McConnell doesn't want it, and the majority leader is very effective at keeping his caucus in line. Two of the president's most prominent Republican critics in the upper chamber, Jeff Flake and Bob Corker, have now retired; another, John McCain, is deceased. That leaves only Ben "I'm going to do everything Trump wants while groaning about 'civility'" Sasse and the newly sworn-in Mitt Romney as possible votes. Assuming there are no Democratic defectors — and there is good reason to believe that Joe Manchin of West Virginia and perhaps one or two others would break rank — and that Bernie Sanders and Angus King, the two independents, vote to convict, Romney and Sasse's treachery would bring the total to 49, well short of the necessary two-thirds super-majority. It's never going to happen.

Scenario 2: The House votes to impeach Trump, but he is not convicted and removed from office by the Senate.

This is unlikely not because I doubt that McConnell and co. would give their man a pass — see above — but because I find it almost impossible to imagine Pelsoi putting her party through something like this. The grassroots would love it. It would raise hundreds of millions, possibly billions of dollars. But Democrats can do all of those things anyway by merely flirting with the possibility of impeachment while subjecting Trump and his associates, past and present, to a series of pointless show-boating hearings. The template for this scenario was established by Republicans in Barack Obama's second term. Pelosi will follow it.

Scenario 3: The House votes to impeach Trump, but the Senate does not hold a trial.

I am not the only person who thinks this is possible. It is not totally unprecedented for the Senate to refuse to vote on the House's impeachment, but it has also not happened since the 18th century, when the upper chamber concluded that William Blount, himself a senator, was not an officer of the federal government. Impeachment proceedings themselves are rare, however, and there is no reason to think that there could not be more anomalies to be teased out of the process. And if recent history has shown us anything it is that if "Cocaine" Mitch McConnell doesn't want to take up certain business in the chamber he controls, nobody is going to make him. This is what I expect to happen if Democrats do end up impeaching Trump. It would be preferable rhetorically speaking for Pelosi to be able to complain about McConnell's perfidy without having to face the prospect of a no vote. If something accomplishes nothing while saving face for both of our major political parties, it's a safe-enough bet.

Scenario 4: The House does not move to impeach Trump.

This scenario assumes that Pelosi is able to keep her people totally muzzled. Given the current breakdown of the House Democratic caucus between cynical careerist neoliberals and doe-eyed freshmen progressives, this doesn't seem to me totally impossible. If you're a newly elected Democrat, why risk the speaker's ire over something doomed to fail anyway? Save her good will for some quixotic green jobs bill that the Senate will also defeat instead. Besides, the endless Russia hearings are probably going to be enough to tide the base over until 2020, at which point everyone's focus will shift to defeating Trump at the ballot box rather than on Capitol Hill.

Scenario 5: The House holds one or more votes to impeach Trump that fail.

This has in fact already happened. In December 2017, Rep. Al Green (D-Texas) introduced articles of impeachment that named, among other high crimes and misdemeanors, one of the president's tweets about football players and his description of a political opponent as "wacky." It failed overwhelmingly. Pelosi will do her best to keep her caucus from embarrassing themselves, but the likelihood that November 2020 rolls around without another failed impeachment vote seems low. This is the safest bet of all.