Off the trail on Friday, Ms. Haley assailed Mr. Trump as “unhinged” on Fox News as she continued to try and bait him into a one-on-one debate. The presidential primary features Ms. Haley on the ballot, but won’t count toward the G.O.P. The caucuses feature Mr. Trump without a single major competitor — and that’s the contest that will determine who gets the state’s delegate prize. Critics have argued that the state party set up the caucuses to benefit Mr. Trump — which the party denies. The former president and his team were hoping his showing there would persuade Ms. Haley to end her campaign.

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Persons: Donald J, Trump, Biden, Nikki Haley, she’s, Haley, Mr, ”, “, — Nikki, ” Steven Cheung, —, Critics, Jeremy Gelman, Haley’s, Kamala Harris, Ms, Harris Organizations: Republican, Fox News, America, Trump, University of Nevada, Democratic Locations: Nevada, New York City, Reno, New Hampshire, South Carolina, Las Vegas