President Obama’s final State of the Union address Tuesday night was notable both for its allusions to at least four Republican presidential primary candidates—Donald Trump, Ted Cruz, Marco Rubio, and Jeb Bush—and for the relative extent to which it concerned itself with each one.

Obama made no secret of his distaste for George W. Bush-like military adventurism, or for Republican politicians who attack food stamps—and anyone following the campaign closely recognized those moments as oblique attacks on Rubio and Bush, respectively. But Obama devoted more rhetorical effort to denouncing Cruz, and far more still to denouncing Trump.

If this was a reflection of Obama’s desire to elevate Trump, casting him as the guiding force of Republican politics for obvious political reasons, it was also a reflection of the disquieting reality that, as Talking Points Memo’s Josh Marshall wrote recently, “Trump is not only not winning the primary race as of now but dominating the race like no non-incumbent has in modern history.”

It’s against this backdrop that establishment Republicans are stepping up their efforts to weaken Trump, and doing their best to discourage attacks on Rubio. Party leaders picked South Carolina Governor Nikki Haley, a daughter of Indian immigrants who condemns Trump’s demagoguery, to deliver the official State of the Union response. And party strategists have lined up to defend Rubio from establishment attacks—even as Rubio attacks other establishment candidates—because they recognize Rubio is the strongest non-insurgent candidate in the field. 

But in the end, these are tacit admissions that Obama has distilled the race down to its essence. Trump really is setting the tone for the Republican Party, and candidates like Rubio and Bush are not. 

Thursday night’s Republican primary debate—less than three weeks before the Iowa caucuses—is one of the candidates’ final opportunities to scramble the picture. But absent manna falling from heaven to devastate Trump and deliver Rubio a career-making performance, it’s hard to see how anything anyone might do between now and the end of the month can turn the race on its head before February 1.

The central problem Republican elites face is that their favored candidates (Rubio and Bush, but also John Kasich and Chris Christie) both outnumber Cruz and Trump, and are fighting amongst themselves over a smaller and shrinking portion of the GOP electorate. 

For a candidate like Rubio to get to anywhere near Trump-levels of support, every other candidate in the so-called “establishment lane” would need to concede, and their supporters would need to defect to him overwhelmingly. Instead, the candidates are actively tearing each other down in a Hunger Game to emerge as the sole tribute of the establishment, perhaps souring their own supporters on the alternatives along the way. 

Rubio and Christie are attacking one another bitterly, while Bush and his massive SuperPAC Right to Rise are trying to destroy Rubio. It does Rubio little good to emerge as the winner of these fights if Christie’s supporters break for Trump, and if Cruz-curious Rubio supporters respond to Bush’s attacks by defecting to the Texas senator. That’s especially true if you assume voters who continue to support Ben Carson, Carly Fiorina, Mike Huckabee, and the rest are more favorably disposed to Trump and Cruz than to Rubio or anyone else in the “establishment lane.”

That “establishment lane,” in other words, is a total mess. It has reached a point where the least far-fetched scenario for a party-insider comeback involves Rubio failing to win in Iowa, failing to win in New Hampshire, and failing to win South Carolina, then somehow managing to pull it together in time to win the Nevada caucuses, despite trailing badly there, too. As implausible as this sounds, it also requires assuming Trump and Cruz benefit in no meaningful way from their early victories, or from the presumed departures of Bush, Kasich, Christie, Fiorina, Huckabee, Carson, Rick Santorum, and Rand Paul.

This is a comically narrow path. Narrower even than Trump’s, which runs through winning several early contests, and then winning many later ones.

To widen it, Rubio needs to pull himself out of his ongoing political skirmishes with Christie and Bush, and do what nobody else thus far has been able to do with consistent success: draw down Trump’s and Cruz’s support by winning over their supporters. It’s unlikely all of that will transpire in just one debate. But if none of it does—if Rubio gets drawn back into arguments with lower-tier candidates, and Trump and Cruz continue to over-perform—it will be time for party insiders to stop fantasizing about a comeback narrative, and start thinking about which of two evils they fear less.