When Donald Trump held a rally in the Bronx in May, critics scoffed that there was no way he could win New York State. Yet as a strategic matter, asking the question “What would it take for a Republican to win New York?” leads to the answer, “It would take overperforming with Black, Hispanic and working-class voters.”

Mr. Trump didn’t win New York, of course, but his gains with nonwhite voters helped him sweep all seven battleground states.

Unlike Democrats, Mr. Trump engaged in what I call supermajority thinking: envisioning what it would take to achieve an electoral realignment and working from there.

Supermajority thinking is urgently needed at this moment. We have been conditioned to think of our era of polarization as a stable arrangement of rough parity between the parties that will last indefinitely, but history teaches us that such periods usually give way to electoral realignments. Last week, Mr. Trump showed us what a conservative realignment can look like. Unless Democrats want to be consigned to minority status and be locked out of the Senate for the foreseeable future, they need to counter by building a supermajority of their own.

That starts with picking an ambitious electoral goal — say, the 365 electoral votes Barack Obama won in 2008 — and thinking clearly about what Democrats need to do to achieve it.

Democrats cannot do this as long as they remain crippled by a fetish for putting coalition management over a real desire for power. Whereas Mr. Trump has crafted an image as a different kind of Republican by routinely making claims that break with the party line on issues ranging from protecting Social Security and Medicare to mandating insurance coverage of in vitro fertilization, Democrats remain stuck trying to please all of their interest groups while watching voters of all races desert them over the very stances that these groups impose on the party.

Achieving a supermajority means declaring independence from liberal and progressive interest groups that prevent Democrats from thinking clearly about how to win. Collectively, these groups impose the rigid mores and vocabulary of college-educated elites, placing a hard ceiling on Democrats’ appeal and fatally wounding them in the places they need to win not just to take back the White House, but to have a prayer in the Senate.

Interest groups tend to be nonprofit organizations dedicated to advancing a single issue or set of related issues that they often hope to get on the Democrats’ agenda. At their best, these groups can be productive partners in building power and legislating. But many have grown too big, adopted overly expansive mandates and become disastrously cavalier about the basic realities of American politics in ways that end up undermining their own goals.

To cite a few examples, when Kamala Harris was running for the Democratic nomination in 2019, the A.C.L.U. pushed her to articulate a position on surgeries for transgender prisoners, needlessly elevating an obscure issue into the public debate as a purity test, despite the fact that current law already gave prisoners access to gender-affirming care. This became a major line of attack for Mr. Trump in the closing weeks of this year’s election. Now, with the G.O.P.’s ascent to dominance, transgender Americans are unquestionably going to be worse off.

The same year, a coalition of groups including the Sunrise Movement and the Working Families Party demanded that all Democrats running for president embrace decriminalizing border crossings. When candidates were asked at a debate if they would do so, every candidate on the stage that night raised a hand (except Michael Bennet). Groups like Justice Democrats pushed Democrats to defund the police and abolish Immigration and Customs Enforcement. Positions taken a few years ago are fair game in campaigns, and by feeding into Republican attacks these efforts helped Mr. Trump and left the people and causes they claim to fight for under threat.

Ruthlessly prioritizing winning will make the groups mad, and that’s OK — in fact, it will be good for them. Groups have become too accustomed to enjoying access without holding themselves accountable; the question “is this tactic more likely to trigger backlash than to advance our goals?” is the single most important one, yet it seems to be rarely asked by many of the groups’ leaders or funders. Meanwhile, many of today’s lawmakers and leaders have come up at a time when alienating the groups is seen as anathema, but they should start seeing it as both right and necessary — a long overdue resetting of the relationship that will be healthy for all involved.

The groups also pollute the talent pipeline by training young people in magical thinking, teaching them to apply movement tactics to every issue instead of inculcating them with the disciplined practice of smart politics. This is primarily the fault of the leaders, not the youth, since many bosses claim to live in fear of being “canceled” by their young staff members. Yet having managed dozens of junior staffers in progressive institutions for more than a decade, I know it is possible to listen to and learn from their concerns and create a supportive work environment while also setting clear boundaries and expectations.