Carl Leubsdorf

Carl P. Leubsdorf, Dallas Morning News

Riding the expectations game is a bit like riding a tiger: It’s hard to keep on top for very long.

That’s what Marco Rubio learned in the New Hampshire primary.

Eight days ago, the Florida senator’s close third-place finish in the Iowa caucuses sparked both fears among fellow GOP candidates that he might outflank them to become Donald Trump’s major rival and concerns among Democrats that the GOP might actually nominate its strongest potential standard bearer.

But in last Saturday’s GOP debate, Rubio froze under the pressure of a fierce verbal assault from New Jersey Gov. Chris Christie. When New Hampshire Republicans voted Tuesday, Trump won easily. Rubio’s hopes of running second faded to a disappointing fifth-place finish.

As a result, Rubio faces an uphill fight in the coming South Carolina primary and Nevada caucuses.

And concerned Democrats might feel a bit better.

To be fair, the New Hampshire results showed that Democrats have their own serious problem. The breadth of Sanders’ victory over Hillary Clinton signals a long, drawn-out primary battle. The former secretary of state’s onetime inevitability no longer seems so inevitable.

That can hardly please the Democratic establishment, which is heavily committed to Clinton and worried about what would happen if the party nominated a 74-year-old, self-styled democratic socialist.

That fear is offset, at least for now, by the fact that, once again, two of the three GOP leaders were Trump and Texas Sen. Ted Cruz, who even Republicans fear would be weak general-election candidates.

Trump’s smashing victory, more than doubling the vote of his closest rival, confirmed his position as the Republican to beat. And though New England is hardly favorable territory for the outspokenly conservative Cruz, the Iowa winner showed he remains someone to be reckoned with by finishing third.

Even so, the combined vote won by Ohio Gov. John Kasich, Rubio, former Florida Gov. Jeb Bush and New Jersey Gov. Chris Christie was far more than Trump got, suggesting Republicans are headed for a lengthy three-way race if one of them can consolidate that support.

Christie dropped out Wednesday, having finished sixth in New Hampshire, and so did Carly Fiorina, who finished seventh.

Now headed for the Feb. 20 South Carolina primary, Rubio has vowed he won’t repeat last Saturday night’s halting debate performance, in which he responded to Christie’s accusation of being too inexperienced and too programmed by repeating the same criticism of President Barack Obama, nearly word for word, three more times.

The fact that Kasich, Bush and Rubio all remain in the race will make it hard for any of them to beat either Trump or Cruz in South Carolina.

Foreshadowing the bitter campaign for survival that’s about to unfold, Rubio aide Alex Conant suggested Trump can’t be beaten if Bush stays in the race. Meanwhile, a Bush staffer disparaged Kasich’s long-term chances.

Yet Kasich, by finishing second, kept alive his hope of maintaining his candidacy until the race reaches Michigan and his home state of Ohio next month.

On the other hand,the reality is that he received a smaller percentage of the GOP vote than former Utah Gov. Jon Huntsman did in 2012. Huntsman’s candidacy, with a moderate tone similar to Kasich’s, flamed out after he finished third in New Hampshire.

Kasich has a stronger financial base and is a more substantial figure within the GOP than Huntsman, but he confronts significant obstacles in South Carolina and other even more conservative Southern battlegrounds.

On balance, the night’s biggest Republican loser was Rubio.

“Young Marco Rubio is in trouble,” said Republican strategist Alex Castellanos, a fellow Cuban-American who has been critical of Trump and Cruz and friendly to Rubio. “He was exposed, even though he is right and Chris Christie is wrong: Barack Obama was not too young to be an effective president.”

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