What would happen if Republicans win the midterm elections?

Without a time machine, there’s nothing that can tell us with certainty what’s going to happen in the midterm elections, but there are plenty of metrics — polls, fundraising, historical trends, registration advantages, etc. — that can tell us what’s probable. And with 11 days remaining before Election Day, Democrats are likely to win a House majority, while Republicans are likely to keep the Senate.

It’s understandable that many remain skeptical. After all, Hillary Clinton was favored to win the presidency two years ago. It wouldn’t take much of an electoral shift to produce results that are out of step with expectations.

All of which raises the possibility of Republicans holding onto all of the levers of federal power for another two years.

GOP officials effectively take it as a given that their Senate majority will be larger in the next Congress — NRSC Chairman Cory Gardner believes a 55-seat majority is within reach — and the Associated Press reported this week that leading Democrats “now fear the battle for the House majority will be decided by just a handful of seats.”

The New York Times‘ David Leonhardt had a piece the other day on the implications of a successful GOP cycle.

If Republicans do manage to keep both chambers of Congress, it would cause a political shock…. It’s important to understand that a Republican victory would also change Washington.

It would be validation for Trump, who could then brag that he had defied the experts once again. It would mean he had outperformed Barack Obama, Bill Clinton, Ronald Reagan, Lyndon Johnson and Harry Truman, all of whom suffered drubbings in the first midterm election of their presidency. It would embolden Trump to push even harder toward the America he wants — where corporate oversight is scant, climate change is ignored, voting rights are abridged, health care is a privilege, judicial independence is a fiction and the truth is whatever he says it is.

That sounds … about right.

Leonhardt fleshed out his thesis by shining a light on a variety of developments he’d expect to see in the event of two more years of Republican rule, but there are basically four key areas that I’d recommend keeping an eye on:

* Health care: Mitch McConnell has already said GOP lawmakers will try again to repeal the Affordable Care Act if they have the chance, and last night, Fox News’ Sean Hannity, a close Donald Trump ally, said, “I guarantee you that Obamacare will be repealed and replaced” if there’s a Republican majority.

* Taxes: The president has spent much of the last week touting a new tax plan that exists only in his imagination, but under GOP control, Congress would almost certainly pursue more tax breaks. In fact, remember that after Republican gains in the 2002 midterms, Dick Cheney said massive new tax cuts were the appropriate reward for the party’s success.

* Judges: With extraordinary speed, Republicans have confirmed dozens of new far-right jurists, and Trump nominees now represent one-seventh of the federal judiciary. With two more years of a GOP-led Senate, Republicans will make even more progress on dramatically overhauling the entire branch of government.

* Russia: Special Counsel Robert Mueller’s investigation is ongoing, though that could change. Leonhardt’s piece argued that Republican successes in the midterms could give Trump “the confidence to shut down the investigation, through firing some combination of Mueller, Rod Rosenstein (who oversees Mueller) and Jeff Sessions, the attorney general. In their place, he could install loyalists unconcerned with the quaint notion that no one is above the law. An expanded Senate majority could ease the confirmation of those loyalists.”

There are plenty of concerns among Democratic officials about whether the party’s supporters will show up this election season. Given the stakes, I’m not sure what more motivation they’d need.