Nikki Haley is cutting into Donald Trump's lead in a crucial early voting state. Will it be enough?

Support for Republican presidential candidate and former South Carolina Gov. Nikki Haley is surging in New Hampshire a month from the state’s first-in-the-nation presidential primary. 

Almost a third of Granite State voters likely to cast a ballot in New Hampshire's Republican primary named Haley as their preferred candidate in a Saint Anselm College poll released this week.

Haley has doubled her support in the state since September, according to Saint Anselm’s findings, and she is ten percentage points ahead of where she was in a November CNN/University of New Hampshire survey. 

The former governor is now the clear second choice in the first primary state, but she continues to trail behind former President Donald Trump. Trump led Haley 14 percentage points in the Saint Anselm poll released earlier this month, and he leads all of his Republican rivals in state-level and national polls across the country.

Haley’s mounting momentum, however, comes on the heels of coveted endorsements, including from New Hampshire’s popular Republican Gov. Chris Sununu. 

Sununu’s backing was essential in Haley becoming “the clear alternative” to Trump, Saint Anselm College’s New Hampshire Institute of Politics Director Neil Levesque said in a summary of the recent survey results.  

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Haley's support is particularly strong among “somewhat conservative” and “moderate” Republican primary voters, in a state where independents play a major role in determining candidates’ fates.

And the former ambassador to the United Nations doesn't necessarily have to defeat Trump in the New Hampshire primary to make progress, some experts say. Instead, she needs to get close enough to alter the narrative that he's the runaway favorite in the Republican race ahead of other GOP primary contests, especially in her home state of South Carolina.

“If Trump doesn’t get over 50%, it shows he has serious competition in the party,” Andrew Smith, director of the University of New Hampshire Survey Center, previously told USA TODAY.

Yet Haley still has significant ground to cover as she competes against Trump. Despite cutting his lead in half, Trump’s support in the Granite State has not wavered from the 40% range among Republican voters in the state.

“Trump’s supporters seem undeterred by the former president’s ongoing legal challenges,” Levesque said in the survey release, referencing the four sets of criminal indictments Trump currently faces.

Contributing: Karissa Waddick, USA TODAY