Trump wins New Hampshire Republican primary, AP projects

• His victory is also a blow to former United Nations Ambassador Nikki Haley, whose presidential ambitions hinged on a strong performance in the first-in-the-nation-primary.

The big picture: The New Hampshire primary became a head-to-head race between Trump and Haley after Florida Gov. Ron DeSantis suspended his campaign on Sunday.

• Haley, who won the endorsement of New Hampshire Gov. Chris Sununu, had a surge of momentum in recent months and some polls showed her within single digits of Trump.
• The former president ramped up his attacks against Haley in the run-up to the primary as he sought to quash her momentum.

State of play: Trump won the Iowa caucuses by 30 percentage points and dominated across virtually every demographic. He won all but one of the state's 99 counties.

• New Hampshire has a more diverse electorate than Iowa, with fewer evangelical voters, which made the Granite State a key test of his broad base of appeal to less conservative voters.

Zoom in: Haley, buoyed by late-stage, high-profile endorsements, sought to tap into her appeal to the state's independents voters, who are allowed to participate in a primary of their choice.

• Haley also sought a boost from voters who had supported former New Jersey Gov. Chris Christie, who campaigned heavily in the first-in-the-nation primary state but dropped out this month.

What to watch: The campaign next heads to Nevada, which is hosting a Republican caucus on Feb. 8.

• Trump has said he wants to secure the Republican nomination by Super Tuesday on March 5.

Go deeper: ABC News cancels New Hampshire debate