CONCORD — The campaign to conserve 5,800 acres surrounding the historic Balsams Grand Resort Hotel in Dixville Notch received a substantial boost Friday as an anonymous donor stepped forward with a $150,000 contribution.

With days to go before a Jan. 15 deadline, the Society for the Protection of New Hampshire Forests as of Sunday has raised slightly more than $700,000 toward the $850,000 it needs to acquire conservation restrictions on the iconic landscape, said Jack Savage, spokesman for the Forest Society.

“This is fabulous news,” said Jane Difley, president/forester of the Forest Society. “This generous gift is just the shot in the arm we need as we go into the final week of fundraising. We still have a ways to go, and we need everyone who would like to see the land protected to step forward if they haven’t already. We’re not at the end of our campaign, but we can see it from here.”

Savage said “steady online giving” through the weekend added almost $100,000 more after the $150,000 gift.

“We’re very optimistic” the goal will be attained, he said. “We’ve got to keep going. We have a lot of money to raise in seven days, but we’re very optimistic.”

The Forest Society has a purchase and sale agreement with the Tillotson Corporation to acquire conservation restrictions on 5,800 acres of land surrounding the Balsams Hotel. The agreement also includes the rights to a transmission line right-of-way sought by Northern Pass Transmission LLC, which wants to cross the Balsams land with a high-voltage line involving towers up to 135 feet high.

The $1.1 billion project would provide power from Hydro Quebec to the New England electric grid over 180 miles of power lines from the Canadian border at Pittsburg to Deerfield.

Tillotson sold the hotel in December and chose to work with the Forest Society to conserve the land rather than sell a right-of-way to Northern Pass.

Northern Pass had offered $3 million for the right-of-way to the Neil Tillotson Trust for the land surrounding the Balsams Resort, but trustees decided in favor of the Forest Society, signing a purchase-and-sales agreement Dec. 6.

Northern Pass challenged the deal, but the Attorney General’s Office responded that the trustees were acting within their rights.

The campaign has drawn contributions from more than 500 people so far, ranging from a few dollars collected at a coffee shop to major gifts, including Friday’s $150,000.

Donations can be made at forestsociety.org/balsams. More information, including a video about the project and a map, can be found at savethebalsamslandscape.blogspot.com.