In recent days, Democrats have been trampling all over each other to get to a microphone to trumpet massive structural changes to American public life.

First, several presidential candidates are calling for an increase in the size of the Supreme Court. Nine justices are too few, apparently. In a proposal that seems straight out of the writers’ room at “The West Wing,” Beto O’Rourke wants the court apportioned by party, with five Democrats and five Republicans, and an extra five chosen by the 10 partisan ones.

Meanwhile, House Speaker Nancy Pelosi has endorsed a proposal to lower the federal voting age to 16 (an idea already being contemplated at the local level in Oregon and the District of Columbia, and gathering steam in California).

Oh, and a great many Democrats want to abolish the Electoral College. This is nothing new for modern Democrats, who feel the Electoral College makes it too hard for them to win the presidency. But there’s never been serious practical discussion of it because it’s pointless to advocate it — 38 states would have to vote to agree to it for the amendment to pass, and as such a move would weaken the political power of small states, that will never happen.

Welcome to the Democratic presidential campaign of 2020. You can expect at least five minutes of every presidential debate to be taken up by that fantasy as well as these others.

Why are leading figures in the Democratic Party tossing around radical and wildly unrealistic proposals the way Tom Cruise mixed drinks in “Cocktail” as they prepare to wage a national battle for the presidency they have reason to believe they can win?

The most obvious answer is that Democrats want to change the rules because they think the rules aren’t working for them. They want the popular vote instead of the Electoral College because they’ve won the popular vote four times out of the past five elections. They want to pack the court because the court is going conservative. And they want the voting age lowered to 16 because they want to stuff the ballot box.

So they have good reason to want what they want. But what they want will require a wholesale revision of our political system. Is it wise for them to be shouting about this from the rooftops?

Democrats did not win a wave midterm election with an astounding 62 million votes nationwide because they said they were going to revolutionize American politics. When it came to policy, they largely focused on health care.

And when it came to general national matters, they were subdued enough to allow voters to use them as proxies to express their discomfort with the cultural revolutionary in the White House. Had they been excessively provocative, 40 seats wouldn’t have switched from Republican hands to Democratic hands.

There are several answers. First and most important is that while 2018 voters might not have craved radicalism from their candidates, the people running for president in 2020 seem pretty convinced Democratic primary voters are hungry for it.

Thus, there’s no downside to making visionary speeches advocating transformational change — especially if the transformational changes are designed to give Democrats and liberals structural control of the political institutions the current system has not allowed them to dominate entirely.

If Democrats running for president are sure that their party’s primary voters have been thoroughly radicalized by President Trump, then it stands to reason those voters aren’t going to judge them harshly for not being prudent and realistic about what they think or what they might promise. Such people do not want to hear about what is prudent and what is achievable. They want to hear “La Marseillaise.”

In the case of Nancy Pelosi and lowering the voting age, something more cynical may be going on. Pelosi said last week she didn’t think trying to impeach Trump was worth it. Since she was taking that piece of raw meat away from her party’s starving mob, she had to throw them another one.

Here’s the thing, though. Eighty thousand votes won Donald Trump the election in 2016 — votes scattered across three states that Barack Obama had won twice.

If you put aside all the high-flown talk about the grand meaning of the Trump victory and what it tells us about America and our history and white supremacy and blah blah blah, the challenge for Democrats in 2020 is pretty simple. They need to get 80,000 new Democratic votes in those places, flip the states, and reclaim the presidency.

They won in 2018 by not being lunatics. Democrats seem intent on testing the proposition that it will take a lunatic to beat a tweeter.