The latest GOP presidential debate demonstrated again that Ron DeSantis and Nikki Haley are pursuing utterly inimical strategies for catching the front-runner, Donald Trump.

The debate, on Wednesday evening, also showed why neither approach looks remotely sufficient to dislodge Trump from his commanding position in the race.

DeSantis delivered a stronger overall debate performance than Haley. But the evening mostly displayed the structural limitations of the theory that each campaign is operating under, and the limited progress either candidate has made toward surmounting those obstacles.

As he showed during the debate, DeSantis is grounding his coalition on the right by defining himself as an unflagging champion for the partys most conservative elements. During the debate, the Florida governors frequent attacks on Haley, and more infrequent (and oblique) jabs at Trump, both represented variations on the charge that neither rival can be trusted to advance conservative priorities.

Haley, in mirror image, is grounding her coalition in the partys center. She has focused on consolidating the centrist GOP voters and donors who have long expressed the most resistance to Trump. That includes moderates, people with at least a four-year college degree, GOP-leaning independents, and suburbanites.

DeSantiss vision, in other words, has been to start on the right and over time build toward the center; Haley wants to grow in the opposite direction by locking down the center, and then expanding into the right.

Supporters of both Haley and DeSantis believe that the others approach lowers their ceiling too much to ultimately topple Trump. The problem for all Republicans looking for an alternative to the former president is that last weeks debate offered the latest evidence that each camp may be right about the others limitations. With the voting beginning only five weeks from Monday in the Iowa caucus, neither Haley nor DeSantis has found any effective way to loosen Trumps grip on the party.

Neither, in fact, has even tried hard to do so. Instead, they have centered their efforts almost entirely on trying to squeeze out the other to become Trumps principal rival. To beat Trump, or to come close, eventually either of them will need to peel away some of the roughly 60 percent of GOP voters who now say in national polls that they intend to support him for the nomination. But both have behaved as if they can leave that challenge for a later day, while focusing on trying to clear the field to create a one-on-one contest with the front-runner.

The theory in DeSantiss camp has been that the only way to beat Trump is to aim directly at his core supporters with a conservative message. DeSantis advisers acknowledge that his positioning has not connected with many centrist voters. But his camp believes that if DeSantis can emerge after the early states as the last viable alternative to Trump, the moderates most resistant to the former president will have no choice but to rally around the Florida governor, even if they consider him too Trump-like himself.

The voters now drawn to Haley share a goal in common with Governor DeSantis in that they want an alternative to Trump, Bob Vander Plaats, a prominent Iowa religious conservative who has endorsed DeSantis, told me. The more that DeSantis proves there is one alternative to Trump, he will start peeling off that lane as well. By contrast, Vander Plaats argues, if DeSantis falls out of contention, his support is more likely to flow back to Trump than toward Haley. I havent heard any supporter of DeSantis yet saying: Im deciding between him and Haley, he told me. Basically, they are between Trump and him.

DeSantiss supporters anticipate that his strategy will pay off if he finishes strongly in Iowa. But so far, his decision to offer voters what amounts to Trumpism without Trump has returned few dividends. With his Trump-like agenda on immigration and foreign policy, and emphasis on culture-war issues such as transgender rights, DeSantis has alienated many of the centrist GOP voters most dubious of the former president while failing to dislodge many of his core supporters.

Ron DeSantis should have consolidated the non-Trump wing of the party from the get go and then gone after soft Trump supporters, Alex Stroman, a former executive director of the South Carolina Republican Party, told me in an email. Instead, he tried to out-MAGA Trump from the right and alienated not only soft-Trump voters but also the more pragmatic wing of the party. It was a strategic blunder.

Haley has filled that vacuum with the elements of the party most skeptical of Trump. Her approach has been to start with the primary voters who like the former president the least, with the hope of eventually attracting more of those ambivalent about him. Her backers believe she has a better chance than DeSantis to reach those maybe Trump voters. As the veteran GOP pollster Whit Ayres told me, DeSantis has tried to appeal to some of the always Trump voters, but the always Trump voters are always Trump for a reason. Nikki Haley seems to have figured out the job is to consolidate the maybe Trump voters who supported Trump twice but now want a different style and different temperament.

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DeSantis still leads Haley in most national polls, though that may be changing. And he remains even or ahead of her in the polls in Iowa, where he has campaigned relentlessly, won support from most of the states Republican leadership (including Governor Kim Reynolds), attracted broad backing in the influential religious-conservative community, and spent heavily on building a grassroots organization.

But DeSantis is in a much weaker position in the other early states. A recent poll by CNN and the University of New Hampshire found him falling to fourth in the Granite State. That poll found Haley emerging as a clear second to Trump, as did another recent CNN survey in South Carolina. In each state, she attracted about twice as much support as DeSantis did. Polls also consistently show Haley running much better than DeSantis, or Trump, in hypothetical general election match ups against President Joe Biden.

All of these positive trends largely explain why DeSantis and Vivek Ramaswamy, another GOP contender, attacked Haley at the debate. Haley was right when she suggested that the attention reflected anxiety in DeSantiss camp about her rise. But that motivation doesnt necessarily make the attacks any less effective.

After delivering the most assured performances in the first three GOP debates, Haley seemed wobbly last week as DeSantis and Ramaswamy pummeled her from the right. Dave Wilson, a longtime Republican and social-conservative activist in South Carolina, told me that Haley had not faced that kind of sustained ideological assault from the right during her career in the state. It hasnt been used against her in South Carolina, Wilson said. Nikki has never been some kind of mainstreamer or a shill for the big corporations. Thats not who she has portrayed herself as, or how she governed, when she was governor of South Carolina.

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At the debate, Haley never seemed to find solid ground when DeSantis accused her of resisting the hard-line approaches he has championed in Florida on issues affecting transgender people. Haley neither embraced DeSantiss agenda nor challenged it and instead insisted he was mischaracterizing her own record, without entirely clarifying her views. Especially on those types of cultural issues, it is probably always going to be advantage DeSantis, Vander Plaats told me. I think if you turned down the volume and just [looked at] the physical appearance, Nikki was very concerned at that point, like she knew she was in a tough space, and DeSantis was in a very confident space.

Her uneasy response on issues of LGBTQ rights was a stark contrast to the confident course she has set on abortion. One reason Haley has gained favor with more centrist Republicans is that she has so clearly argued that the GOP canot achieve sweeping federal abortion restrictions and must pursue consensus around more limited goals. I think Nikki Haley talks about social issues the same way that real people do: not through demagoguery or hysterics like some candidates, but having real policy disagreements while showing compassion for those affectedand I think thats the winning formula, Stroman said.

But at the debate, Haley was unwilling to apply that formula to LGBTQ issues, even as she seemed to seek a more empathetic tone than DeSantis.

She has clearly thought through a more moderate, nuanced position on abortion that would have greater appeal in a general election, Alice Stewart, a longtime GOP strategist who has worked for leading social-conservative candidates, told me. It appears she has not mapped out her position on other culture-war issues, such as transgender procedures and school bathrooms.

Doubling down on his message at the debate, DeSantiss campaign told me afterward that within the confines of the Constitution he would support nationalizing the key laws affecting transgender people that he has passed in Florida, such as banning gender-affirming care for minors. Haleys campaign still appeared focused mostly on deflecting this argument: In comments to me after the debate, her aides stressed that although DeSantis criticized her for opposing legislation as governor requiring students to use the restroom of the gender they were assigned at birth, he similarly indicated that the issue was not a priority for him not long thereafter, during his first gubernatorial campaign in 2018. Their message was that DeSantis is stressing these issues now merely out of expediency. But in an email exchange with me after the debate, Haleys campaign drew a clearer distinction with DeSantis than she did during the encounter: Rather than national action to impose on every state the restrictions Florida has approved on LGBTQ issues, the campaign said Haley would encourage states to pass laws that ban classroom discussion of sexual orientation or regulate bathroom use for transgender kids. The one exception the campaign noted is that, like DeSantis, she would also support national legislation banning transgender girls from competing in school sports.

The debate drew only a small audience and is unlikely by itself to significantly change the trajectory of the DeSantis and Haley competition. Wilson and Stroman both said they doubt that DeSantiss ideological attacks will hurt Haley much in the South Carolina primary. Its going to be harder in South Carolina than he thinks, because everyone knows what Nikki Haley did in this state, Wilson said. Under her leadership, a lot of strong conservative stands were taken.

But, of course, GOP voters dont know nearly as much about Haley in the cascade of states that will vote in early March, after South Carolina. DeSantis supporters view her unsteady response to his ideological assault at the debate as validation of their belief that Haley can never attract enough conservative voters to genuinely threaten Trump. Theres just no path for her to win the nomination, Vander Plaats argued. That lane doesnt exist.

The path for any alternative to beat Trump is a rocky one, but its premature to assume that Haley cannot outlast DeSantis to become the last viable challenger to the former president. She still has time to formulate better responses to the charge that shes insufficiently conservative for the Trump-era GOP. Portraying Haley as too squishy in the culture war might help her in New Hampshire, the state where shes hoping to emerge as Trumps principal rival.

But the debate underscored her need to sharpen her answers on those issues as the race moves on. And for Haleys supporters, it raised an ominous question: If she couldnt respond more effectively to an attack on her conservative credentials from DeSantis and Ramaswamy, how would she hold up if she ever becomes enough of a threat for Donald Trump to press that case himself?