A barometer, said a wit, is an ingenious instrument that reveals the weather we are experiencing. Presidential campaigns often are political barometers. They can, however, change the social climate. The Democratic presidential aspirants, plucking at the electorate’s sleeve, are perhaps inadvertently getting the country interested in moderation.

Many of them spent 2019 detailing how they would wield government as a scalpel to surgically remove America’s blemishes. Inconveniently, but without inhibiting these aspirants, the year ended with a cascade of discouraging headlines about the scalpel: “At war with the truth: How officials put their spin on 18 years of [Afghanistan] setbacks” (Washington Post), “Inspector Accuses FBI Of ‘Gross Incompetence’ in Handling Wiretap” (New York Times), “FAA Knew Boeing’s 737 Max Was Risky But Allowed Flights” (Wall Street Journal). Etc.

As 2020 begins, voters who say that their overriding objective is to remove the current president should wonder: Is it wise to hitch their wagons to any candidate whose agenda radiates, and requires, extravagant confidence in government’s ability to radically rearrange America’s most complex processes, from the allocation of economic resources to the provision of health care?

There is discouraging news for Donald Trump, which means encouraging news for the republic: Sen. Bernie Sanders is showing remarkable resilience, coronary and political, after his October “myocardial infarction.” This is encouraging not because the nation should swap one form of economic illiteracy for another, replacing a florid, angry protectionist with a florid, angry socialist. Rather, it is encouraging because Sanders and Sen. Elizabeth Warren continue to divide, more or less evenly, the “let’s give government lots more to do” constituency. The longer this balance persists, the more time normal — meaning not very agitated or attentive — voters have to rally ’round candidates who do not make prudent people wince.

Now-former Mayor Pete Buttigieg, whose rise has been this political season’s most interesting development, might have the political magic of allowing different voters to see different things in him. This recalls Hamlet having fun with Polonius:

Hamlet: Do you see yonder cloud that’s almost in shape of a camel?

Polonius: … ’tis like a camel, indeed.

Hamlet: Methinks it is like a weasel.

Polonius: It is backed like a weasel.

Hamlet: Or like a whale?

Polonius: Very like a whale.

The Democrats’ nominee might be apparent late in the evening of March 3, “Super Tuesday,” when 14 states allocate about 34% of the delegates to the nominating convention. By that evening, Michael Bloomberg will have learned, to his delight or sorrow, whether political spending is as potent as campaign reform scolds believe, or whether there is a steeply declining utility of the last millions of political spending.

If the nominee will be known that evening, we are already in at least the seventh inning of the nomination game. But the top of the first inning can matter a lot.