"The work goes on, the cause endures, the hope still lives, and the dream shall never die."

Ted Kennedy's old line, delivered at the Democratic National Convention just three short months before Ronald Reagan defeated Jimmy Carter, was intended as a rallying cry for the confident liberalism that had set the tone and agenda for the nation's politics over the previous three decades. But it ended up serving as an elegy.

Nearly four decades later, one can imagine those words being recited as a morale-booster at a meeting of dead-ender Never-Trump Republicans as they mull over who should rise to the challenge of taking on the sitting president in next year's GOP primaries. Will it be Maryland Gov. Larry Hogan? Or Former Ohio Gov. John Kasich? This week we learned that it would be former Massachusetts Gov. (and Libertarian Party vice presidential nominee) William Weld.

Running for president is extremely difficult. Attempting to torpedo a president of one's own party seeking re-election is nearly always something close to a political suicide mission. For all those reasons, we should accord anyone willing to make the attempt a modicum of respect. That certainly holds for Weld.

But that doesn't mean the effort makes sense. In this case, it makes no sense at all. Yes, President Trump is vulnerable in 2020. But he's not vulnerable because the Republican electorate is pining for the opportunity to vote for another Jeb Bush or Mitt Romney — let alone a Jeb Bush or Mitt Romney who, like Weld, is pro-choice. The only kind of Republican who would have a shot of defeating the president in a primary would be a more competent Trumpist than Trump himself.

The tiny faction of the Republican Party that openly loathes Trump enough to want to see him brought down in a kamikaze mission — a faction that enjoys outsized attention because it is vastly overrepresented in the media — has misread him from the start. First these Republicans considered Trump a sideshow and a buffoon whose sky-high poll numbers in the months leading up the start of 2016 primary season meant nothing. Surely the voters would come around and cast ballots for Bush or Kasich or Marco Rubio or Chris Christie or (God forbid) Ted Cruz over the reality-show carnival barker.

Then they assumed Trump's string of early primary victories would give way to defeat once the anybody-but-Trump vote coalesced around a suitable alternative. Then they were sure Trump's clinching of the nomination would be overturned at the Republican National Convention. Then they were convinced he would lose in a landslide to Hillary Clinton. When he didn't, many of them came to believe, finally, that he was certain to be removed from office by impeachment, a Robert-Mueller-facilitated indictment, or the invocation of the 25th Amendment.

They've been wrong every step of the way. And they are wrong now.

There are Republicans who wish Trump would tone down his unpresidential tweeting, and some who are offended by his tabloid bluster. But there are hardly any who are anything other than thrilled with his administration's commitment to cutting taxes and regulations, appointing conservative judges and Supreme Court justices, pulling back from our overseas obligations, and "trigging the libs" on every possible front of the culture war (including some that Trump is single-handedly responsible for opening up).

That's why, even after more than two years of scandal and unprecedented political turbulence in Washington, roughly 90 percent of Republicans approve of the president's performance. That doesn't mean they like him personally or would invite him to date their daughters. It means they like how he's doing his job.

That's true even in New Hampshire, where voters have a history of using their narrative-forming-first-primary-in-the-nation advantage to throw wrenches into the best-laid political plans. While a February poll showed Weld pulling in a not-entirely-humiliating 18 percent against the president, that still left Trump with an overwhelming 82 percent of Republican support. (Since Weld held office just across the border in Massachusetts, he's hardly an unknown quantity in the Granite State.)

By contrast, in the most notorious challenge to a sitting president in recent history, Pat Buchanan managed to win more than double that (37.5 percent) against George H. W. Bush in the 1992 New Hampshire primary. It's become conventional wisdom that Buchanan's challenge to Bush from the right weakened him greatly, preparing the way for Bill Clinton's victory. Indeed, those looking to sink Trump hope that something similar will play out in 2020. There's just one thing missing from the plan: Ross Perot. Were it not for Perot's independent bid for the presidency in 1992, Bush may well have won re-election. It was the one-two punch of Buchanan slamming him from the right in the primaries followed by Perot hitting him from the center that did Bush in.

A centrist-libertarian challenge to Trump in the primaries isn't going to go anywhere. The only thing that would have any (though still very small) chance of success would be a campaign from the same ideological quadrant the president occupies: right-wing populism. It would have to be a Trump without the unpresidential tweets, a Trump who can keep his eye on the ball, who isn't constantly undermining himself with performative contradictions and flagrant displays of rank ineptitude. This doesn't mean the promise of a nicer president. It means the promise of an equally nasty but far more competent president — one who could accomplish even more for the Trumpified right.

That isn't at all what Weld and his allies have in mind.

Donald Trump owns the Republican Party. He has remade it in his own image. We needn't cheer that transformation — I certainly don't — to recognize its reality. Those currently plotting to take him down in the primaries will lose because they have already lost the battle for the party's soul.