CONCORD, N.H. -- Hillary Clinton's campaign has dispatched an army of over 150 staffers from its campaign headquarters in Brooklyn to boost the ground game in early states, primarily in New Hampshire.

The staffers have been driving up from New York to the relatively close Granite State in the final week of campaigning before the Feb. 9 primary.

Clinton faces an uphill struggle to compete with Sen. Bernie Sanders (I-Vt.) here, where polls show he has held a lead.

The Clinton campaign acknowledges that Sanders has an upper hand in the primary, which they attribute to the fact that he is a lawmaker from Vermont, which shares a border with New Hampshire.

"New Hampshire is his back yard and we are behind," the campaign's communications director Jennifer Palmieri said on Tuesday. "Hillary Clinton's way is to fight hard for the vote, and we’ll take it from there."

Some of the dozens of staffers who have left Brooklyn for field work have also been dispatched to Nevada and South Carolina, though the bulk will work in New Hampshire.

According to a campaign aide, the trips -- which were first reported by Buzzfeed News -- had been  planned months ago to coincide with the onset of voting in early states.