THE MORNING PLUM:

Because so many of us got it wrong in 2016, we often adopt a kind of defensive crouch as we interpret the current political moment. We constantly ask whether we’re missing something about President Trump — maybe his abysmally low numbers don’t mean what they ordinarily should; maybe the normal rules of midterm elections really won’t apply this time, because Trump is spreading so much chaos that nothing is conventional anymore. Etc., etc.

But what if the normal rules are on track to holding? What if Trump, despite his small uptick in the polls, really is deeply unpopular, and a backlash against Trump really is the driving factor in our politics right now, just as a backlash against previous presidents drove previous midterm waves enjoyed by the opposition?

A new NBC News-Wall Street Journal poll suggests this might be the case. It finds that Democrats lead among registered voters nationally in the House generic ballot matchup by 50 percent to 40 percent.

But even more tellingly, the poll finds that by a whopping margin of 48-23, voters are more likely to support a congressional candidate who promises to be a check on Trump. And by 53-31, they are less likely to vote for a candidate who has supported Trump’s positions more than 90 percent of the time.

These numbers get more striking when you look at how they break down in all of the House districts that the Cook Political Report designates as competitive. According to the good folks at NBC, who sent over these numbers, in those districts:

  • By 52-19, voters in competitive House districts are more likely to support a congressional candidate who promises to be a check on Trump.
  • By 55-28, voters in competitive House districts are more likely to support a congressional candidate who has opposed Trump most of the time.

It should be noted that the vast, vast majority of these seats are held by Republicans. The seats that this poll designates as competitive are the ones that Cook Political Report rates as Toss Ups, Lean Democratic and Lean Republican. Cook puts 25 seats in the Toss Up categories — 23 GOP-held, and two held by Democrats. Cook puts 27 in the Lean Republican category and seven in the Lean Democratic category — and of that 34, 31 are held by Republicans.

And so, in a whole lot of competitive seats mostly held by Republicans, majorities are more likely to vote for the candidate who will act as a check on Trump and will oppose him on most of his policies.

The poll’s other findings underscore the point. Nationally, Democrats enjoy a large enthusiasm gap: 63 percent of them are extremely interested in the midterms, while among Republicans, that number is only 47 percent. And John Harwood brings us this breakdown of the generic ballot matchup:

Democrats have built that edge on their leads among independents (7 percentage points), voters under 35 (20 points), white college graduates (24 points), Latinos (24 points), and African-Americans (81 points). Republicans retain a narrow edge among whites (3 points) and a large one among white men who have not graduated from college (37 points).

That 24-point edge among white college graduates is striking, and these numbers comport with the story we had been seeing before the generic ballot numbers tightened: Trump has unleashed a large backlash among college-educated whites and younger and more diverse voters — that is, on the other side of the cultural divide from the aging, blue-collar and rural whites that Trump and Republicans hope will be energized enough to allow them to hold the House. If the backlash to Trump is holding, that suggests the conventional rules may hold as well.

It is true that Trump’s approval has ticked up; the new NBC poll has it at 44 percent. But in a way, this underscores the point: That is not far off the approval suffered by other presidents who were hit by wave elections. (Trump is mired closer to 41 percent in the polling averages.) It is also true that the generic ballot has tightened dramatically, and that this is a cause for serious concern. But the FiveThirtyEight average of polls shows that the generic matchup is widening again and it’s now more than seven points. It is possible — no guarantees, but possible — that the NBC poll previews a further widening.

None of this is to predict a Democratic takeover of the House. There could be a wave and Dems could still fall short, due to structural disadvantages and the Democrats’ 23-seat deficit. As Nate Cohn notes, the current environment still suggests a wave, and this still means the battle for the House is roughly a toss-up.

Maybe this doesn’t have to be complicated

But we should not let ourselves get thrown off by the idea that Trump has necessarily rendered all the old rules inoperative. Pundits keep saying Trump is winning the public battle over special counsel Robert S. Mueller III’s investigation, even though majorities side with Mueller, simply because he has convinced Republicans it is a witch hunt, as if that wasn’t inevitable. Pundits keep saying the tightening generic ballot match-up must show that there’s something uniquely challenging about opposing Trump — there are so many objectionable things about him, that it is easy to get baited into overreach, as if attacking his authoritarianism is somehow dangerous.

But perhaps we shouldn’t overreact to the downturn for Dems in the generic House numbers. Perhaps this doesn’t have to be complicated: Trump and his policies are deeply unpopular. Voters know he’s corrupt and authoritarian — those things are two sides of the same coin. They know he lies nonstop and is a racist and has a dangerously destructive temperament. They don’t know the details about the Russia probe, but they think it is legitimately grounded in the rule of law and is investigating genuinely important allegations, they think it will probably produce revelations of wrongdoing and they think Trump is trying to obstruct it. They want a check on Trump’s corruption, policies and temperament — his racist and authoritarian tendencies included. There’s no need for Democrats to shy away from presenting themselves as that check, and by all indications, they aren’t.

* DEM HOPES BRIGHTEN FOR HOUSE TAKEOVER: The New York Times reports that Tuesday’s results in California and New Jersey have improved the Democrats’ chances of taking the House:

Democratic contenders … leveraged financial and strategic help from the national party to … ensure that they will field candidates in multiple districts that they will most likely need if they are to win control in November. … Between California and New Jersey, Democrats will contend for at least 10 Republican-held seats, nearly half of the 23 they need for control.

And of course, there are dozens and dozens of other races in play beyond those two states. But every little bit will matter, because, let’s face it, this is still basically a toss-up.

* DEMS ARE NOMINATING WOMEN AND MINORITIES: The Post’s Michael Scherer brings us this fascinating breakdown:

Voters have cast primary ballots in 32 of the 56 Republican-held House districts most vulnerable to a Democratic takeover, according to the nonpartisan Cook Political Report. Of the 28 races that have been called, Democratic women have won in half the districts … The party’s nominees in these crucial districts also include six military veterans and seven nominees who are black, Latino or Asian.

We are seeing a new generation of Democratic leaders entering politics, largely due to Trump.

* HERE COMES SHOWDOWN OVER ‘DREAMERS’: CNN’s Lauren Fox and Tal Kopan report that House Republicans will meet today in search of a compromise protecting the “dreamers.” A key sticking point:

Moderates have insisted that those individuals have a way to make their status in the US legal. Conservatives have derided anything they label a “special path” to citizenship that would only be available to a specific population.

And it’s still unclear what conservatives — and Trump — will insist on in concessions, such as deep cuts to legal immigration. If this fails, the discharge petition could move forward.

* BORDER CROSSINGS KEEP RISING: Nearly 52,000 people were arrested trying to cross the southwest border in May, according to new federal data, and here’s what it means:

The arrests in May — the third month in a row of increases — follow the Trump administration’s … “zero tolerance” policy that … has resulted in hundreds of children being separated from their parents. The new arrest data suggests such measures have not deterred migrants, many of whom undertake the long trek from Central America to escape violent gangs and drug cartels.

This will get Trump very, very angry. One thing it will not do is get him to reconsider this policy.

* INTERFERENCE WITH PROBE CONTINUES: The Post’s Devlin Barrett reports:

The Justice Department plans to brief senior lawmakers next week with additional details and documents about how the FBI investigated whether Trump campaign advisers had suspicious ties to Russia — a concession to Republican demands for more information about the politically charged probe.

This is your regular reminder that Trump’s nonstop attacks on law enforcement really are eroding its independence, even if the public isn’t siding with him.

* TRUMP UNHAPPY ABOUT TRIP TO CANADA: It turns out that Trump isn’t exactly happy about his coming trip north:

The president has vented privately about Canadian Prime Minister Justin Trudeau … He has mused about finding new ways to punish the United States’ northern neighbor in recent days, frustrated with the country’s retaliatory trade moves. And Trump has complained to aides about spending two days in Canada … believing the trip is a distraction from his upcoming Singapore summit.

Who knew managing U.S. relations with the world could be so complicated and time consuming?

* AND TRUMP TESTS THE MEDIA, BIGLY: E.J. Dionne Jr. gets this exactly right:

Our chief executive instinctively knows what Alexander Hamilton taught long ago: that the despot’s “object is to throw things into confusion that he may ‘ride the storm and direct the whirlwind.’ ” … Trump tests journalists and news consumers in a way they’ve never been tested before. Like would-be autocrats elsewhere, Trump is pursuing a strategy of disorienting the citizenry with a steady stream of provocations, untruths and diversions. We cannot afford to treat any of this as the usual spin or garden-variety politics.

People keep saying progressives attack the media as too pro-Trump. But the real criticism is that too few journos will publicly acknowledge Trump’s deep hostility to basic values of objective truth-seeking.