Over the weekend, President Trump bashed his attorney general for refusing to place Republicans above the law.

To be clear, Trump did this explicitly. In two tweets, Trump slammed Jeff Sessions over charges brought against two Republican members of Congress, an apparent reference to two of his earliest congressional supporters, claiming this would now place their seats in doubt this fall. “Good job Jeff,” Trump raged.

In so doing, Trump inadvertently crystallized the argument for a Democratic-led House: He flatly and openly stated that the rule of law should not apply to Republican members of Congress, particularly his own supporters, because applying the law to them makes a Democratic takeover of the House (which means real accountability for Trump as well) more likely.

A new Post-ABC News poll strongly suggests that this kind of talk from Trump is only hurting Republicans, particularly in many of the GOP-held districts that Democrats need to win to take the House: It finds that a solid majority of voters wants a Democratic-led House to act as a check on Trump. And it finds a big swing in this direction since July.

The Post-ABC poll shows Democrats leading the generic House ballot match-up, 52 percent to 38 percent, among registered voters. The Democrats’ lead is now over 10 points in the polling averages, which suggests that the Democrats’ edge may be currently growing.

Notably, the Post-ABC poll also finds that by 60-34, voters want a Democratic-controlled Congress to act as a check on Trump as opposed to a Republican-controlled Congress that will support Trump’s agenda. This is up from 52-38 in mid-July, a swing of 12 points toward wanting a check on Trump. (Previous polls have found that majorities in the competitive House districts want this as well.)

What’s more, the new Post-ABC poll suggests that the anti-Trump backlash we’ve seen throughout this cycle among suburban, college-educated and independent voters is running strong: According to the cross-tabs, college-educated whites want a Democratic-led Congress as a check on Trump by 62-34, and suburban voters want the same by 58-37. Independents want a check by 63-27.

This could loom large, because many of the GOP-held districts that are key to a Democratic takeover are suburban and college-educated ones. The Post-ABC poll finds that Democrats lead in the generic ballot match-up among suburban voters by 52-40, and among college-educated whites by 53-39.

What Trump is really arguing

When Trump raged against Sessions for refusing to place his GOP supporters in Congress above the law, thus making a Democratic takeover more likely, he was, of course, really raging about the impact this threatens to have on him.

Rep. Devin Nunes (R-Calif.) neatly gave away the game in private remarks that were recently caught on audio. Nunes warned that maintaining the GOP majority is imperative as a last line of defense for Trump, given that Sessions has recused himself and that special counsel Robert S. Mueller III’s investigation continues. In other words, the Justice Department and the GOP-controlled Congress — institutions that are supposed to function as mechanisms of oversight and accountability — are actually seen by Trump and his supporters ideally as concentric rings of defense around the president.

Trump is now expected to fire Sessions after the midterms for the explicitly declared reason that Sessions has not protected him from Mueller’s investigation — as the president has publicly and privately demanded — in order to replace him with a loyalist who will faithfully carry out that task. Whether or not that is successful, looming behind that is the increasing likelihood of a Democratic takeover of Congress, which would mean serious oversight and possibly impeachment next year.

Thus, Trump’s latest attack on Sessions merely expands his indictment of his attorney general’s disloyalty in this regard: Not only has Sessions failed to defend him from Mueller, but he is also imperiling the GOP majority, and with it, Trump’s last-resort line of protection.

With varying degrees of explicitness, some Republicans are actually making this argument as a reason for keeping them in charge of Congress. Trump remains deeply unpopular, particularly among the independents and college-educated whites who could matter this fall: The new Post-ABC poll finds his approval at 38-60 among overall registered voters, at 35-59 among independents, and at 33-64 among college-educated whites. Plus, the tax-cut plan is a total political bust. So all that’s left is to energize GOP voters with race-baiting appeals about immigration and authoritarian attacks on Mueller and the “fake news” media.

But all that actually helps build a very good case for voting Republicans out. The Post-ABC poll also finds that majorities support the Mueller investigation and believe Trump is guilty of wrongdoing, including engaging (in the process of interfering with the Russia probe) in obstruction of justice. And as noted above, large majorities — including among college-educated whites and independents — want a Congress that will check the president.

The more Trump rages against the mechanisms of accountability to motivate his own voters to rally to his defense against them, the more he reminds everyone else precisely why we urgently need a Democratic-controlled Congress — that is, real accountability — more than ever.