Columnist

With control of Congress, the White House and a majority of state governments, the Republican Party can claim to be stronger than at any time since 1928. On the other hand, many Democrats believe that their party's edge among younger voters and growing nonwhite demographic groups has them on the brink of a new reign of power.

The truth is, both parties are in crisis — and may be headed for worse.

The Republican ascendancy is riddled with asterisks. The party's control of Congress has only exposed deep and bitter divisions, as the pirates of Breitbart and talk radio turn their guns on House Speaker Paul D. Ryan (Wis.) and Senate Majority Leader Mitch McConnell (Ky.). Too riven to redeem its oft-sworn pledge to repeal and replace Obamacare, the fractured majority is now struggling to unite around tax cuts, the golden calf of the GOP. As the saying goes, power is what power does — in this case, not much.

At the White House, Republicans rule in name only. The man in the Oval Office owes zilch to the party, having mowed down more than a dozen GOP leaders representing every band of the party's ideological spectrum in his 2016 coup. In office, he continues to train his Twitter flamethrower on Republicans much of the time. Meanwhile, the state-level GOP is waging civil war from Alabama to Arizona.

The internal bloodletting is at least as fierce, though perhaps less public, among Democrats. They, too, nearly lost control of their presidential nomination last year. Sen. Bernie Sanders (I-Vt.) showed scant desire to be a Democrat through his long political career in Vermont, but he has decided late in life to pursue an ideological takeover. The septuagenarian revolutionary continues to galvanize the left wing against leading Democrats, and neither he nor his people are interested in making nice.

In California, for example, veteran Sen. Dianne Feinstein's announcement that she would seek a fifth full term provoked howls from the Sanders set. The former mayor of San Francisco is too centrist for them. Emboldened, the top-ranking Democrat in the state Senate, Kevin de León, has jumped into the primary. Although he may not be as progressive as the left would prefer, the mere fact of his challenge in the heart of Democratic America will cast a klieg light on party disunity.

What makes today's conflicts inside the major parties different from intramural elbow-throwing in the past? The rapid rise of unmediated democracy, enabled by the digital revolution.

For generations, the major parties have served as rival department stores anchoring opposite ends of America's political shopping mall. They chose which products to offer and favored certain ones with their most prominent displays. They marshaled big budgets for advertising and thus loomed over the boutiques and specialty stores — the greens, the libertarians and so on — serving smaller clienteles.

Smartphones and the Internet are killing big retail by connecting buyers directly to products. The same is in store for the major parties. Donald Trump went directly to the voters through Facebook and Twitter; they, in turn, swept him past Republican gatekeepers to commandeer the mannequins and display cases of the GOP. Likewise, Sanders has found plenty of volunteers and cash to support his attempted hostile takeover of the Democratic Party.

Voters no longer need — nor, in many cases, want — a political party to screen their candidates and vet their ideas. They prefer to build their own movements, often with stunning speed. The change is not limited to the United States. Britain's major parties didn't want Brexit, but it's happening. Major parties in France didn't want Emmanuel Macron; now he's president.

America's winner-take-all elections strongly favor the two-party system. (Parliamentary systems, with their proportional representation, encourage smaller, more numerous, parties.) But unless the Republicans and Democrats find ways — pronto — to adapt to the rise of unmediated democracy, their systemic advantage could become an Alamo where defenders of party discipline and coalition-building make their doomed last stand.

Already we've seen a party lose possession of its most precious commodity: its presidential nomination. We've seen a rump minority in the House bounce former speaker John A. Boehner from his post and cast a hungry eye on his successor. In Kansas in 2014, an independent businessman, Greg Orman, cowed the Democratic Party into sitting on the sidelines of a U.S. Senate race. He's thinking about trying it again in next year's gubernatorial election.

Whether the future belongs to independent candidates connecting with voters outside the parties or to Trump- ­inspired hostile takeovers of nominations (probably it will be a combination), the future is dim for the major parties as we've known them. They were too often arrogant, unresponsive and borderline corrupt, but they vetted candidates, gave them training and fostered the compromises that hold teams together. We may miss them when they are gone.

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