Republicans want to keep the House Speaker’s gavel, but far more important is the power to confirm conservative successors to judges like Anthony Kennedy. Photo: Eric Thayer/Getty Images

The battle for control of the U.S. House has been the focal point of political chatter heading toward the November midterm elections, and for good reason. For one thing, it’s a truly national election, with all 435 seats theoretically up for grabs. For another, House elections are generally referendums on the sitting president, and everyone is curious to see whether he will be administered an undeniable rebuke by the public for his many outrages.

But at this particular point in history, what Republicans want most is to maintain or even expand their margin of control in the Senate. That’s partially because it’s a much better investment of time and money. Whether or not they lose control of the House, they are almost certainly going to lose enough seats to make passage of major legislation in that chamber regularly problematic. With the one legislative accomplishment they just had to have — a tax-reform bill — already in the bag, being able to do more before an apocalyptic 2020 election might be desirable, but not absolutely mandatory. And the Senate’s where they failed legislatively in any event.

But the main reason for a Republican focus on the Senate this year is that it’s, relatively speaking, a downhill ride as opposed to an uphill battle. David Wasserman explains the wildly different House and Senate landscapes in a simple statistic:

Fact: if all '18 election results were an 8% pro-Dem uniform swing vs. '16 prez results, Dems would gain 44 House seats & lose 4 Senate seats. — Dave Wasserman (@Redistrict) April 13, 2018

That’s right: Even a Democratic “wave” election could produce Republican gains in the Senate if the partisan polarization of recent years intensifies and Democratic senators succumb to the partisan composition of their electorates. That’s how skewed the Senate landscape is this year.

All things being equal, that’s fine with serious conservatives. The Senate’s the ball game, thanks to its role in confirming Trump’s lifetime judicial appointments. To an extent that is only intermittently understood by liberals, Donald Trump’s fidelity to his promise to appoint federal judges — and particularly Supreme Court judges — that meet the most exacting standards of conservative orthodoxy has been the most important source of conservative support for this president, rivaled only by his willingness to sign the 2017 tax-cut bill. And that was true even before the 2016 election, when believing in Trump’s trustworthiness on judges was a real gamble, as Russell Berman noted at the time:

[A]s they face an uncertain future in which demographic trends will make the nation younger, more diverse, and thus more favorable to Democrats, conservatives view the Supreme Court as a final bulwark they must defend at almost any cost. “We are only one justice away from losing our most basic rights, and the next president will appoint as many as four new justices,” Cruz wrote in the Facebook postannouncing his belated endorsement of Trump. The “basic rights” he was referencing include the right to bear arms, religious liberty, and free speech—as conservatives see them. And of course, the conservative dream of overturning Roe v. Wade would die for another decade or more if the court shifts left.

With Trump in the White House, Neil Gorsuch on the Supreme Court, and a vetting process for judicial nominees firmly in place that gives the Federalist Society a whip hand that conservatives under Reagan or either Bush could have only dreamed of, yesterday’s shield has become a sword, and one more SCOTUS nomination could produce a revolution in constitutional law, beginning with a Roe v. Wade reversal that has been the most important goal for the Christian right foot soldiers of the Republican Party for decades. Whether or not Anthony Kennedy retires from the Court this year (as is persistently rumored, without much real evidence), the odds of Kennedy (81 years old) and Ruth Ginsburg (85) and Stephen Breyer (79) all holding on until 2021 are mixed at best. And so controlling the Senate, and if at all possible obtaining a majority that doesn’t rely on pro-choice Senators Susan Collins and Lisa Murkowski, is the prime objective for many conservatives.

More generally, the point Berman made in 2016 becomes truer each day: Stacking the judiciary is the best imaginable firewall conservatives can build against adverse demographic and public-opinion trends. Yes, the constitutional arrangements that give small states and rural areas disproportionate power in our system will always help the conservative faction in American politics punch above its weight. But that power can be enormously enhanced by judges who oppose campaign-finance restrictions, voting rights for poor people and minorities, and democratically devised regulations on the corporate sector.

So for both short-term and long-range reasons, Republicans have more to gain and lose in the Senate than House elections this year — and a far easier path to success. At present, the main reason control of the House matters much at all (assuming, as I do, that “control” by Republicans would mean a tiny margin giving the House Freedom Caucus a total veto on any legislation whatsoever) is that a Democratic House would add to the investigatory firepower already aimed at the president and his public and private-sector associates. In the end, though, it may matter as much that staunch Trump supporters have an absolute veto power over any impeachment trial in the Senate.

In high-stakes politics you hate to concede any important turf, and Republicans will fight like cornered badgers to keep the Speaker’s gavel in their hands. But when push comes to shove, the Senate is their citadel, offering a high protective wall against even a high wave.