Fabienne Bruneau, a 25-year-old in Murray Hill, raised more than $10,000 for the Crohn’s and Colitis Foundation of America for the marathon and said she did not want to let her supporters down by not completing the race, but she said she understood the decision made by the organizers. Bruneau had not had power since Monday evening, shuttling between coffee shops to charge her phone and laptop, frequenting a gym outside her neighborhood to stay on her training plan and cooking pasta by candlelight in the days leading up to the race.

“I do think that New Yorkers spoke up and they were listening to the people of New York,” Bruneau said. “With the threat of protesters, I’m sure there were concerns about runner safety and I felt uncomfortable with the idea of less police and more people up in arms.”

Eileen Vega-Lamboy, a marathoner from West New York, N.J., and a member of New York Road Runners, said she was planning to run in the race with three members of her family. But after Hurricane Sandy hit and opposition to the event swelled, Vega-Lamboy and her group launched a Facebook group to encourage runners to forgo the race and instead do volunteer work in the hardest-hit areas this weekend.

“We’re very happy with the decision,” Vega-Lamboy said Friday evening. “We still plan to volunteer on Sunday and help out. We’re happy to have it be a day of volunteering and we have people who agreed to donate meals.”

Eline Oidvin, 35, from the rural town of Tau, Norway, came to New York hoping to finish her second marathon. It was a tremendous burden. Visually impaired, she needed a guide to train for many months and a guide to accompany her to New York. Oidvin, a physical therapist with two children, used her savings and donations from her family, spending about $7,500 to fly to New York and pay for hotels and other expenses.

“It’s not a problem for me to understand why they are canceling it,” she said in her Midtown hotel after hearing about the cancellation. “I more than understand for the people who have lost their homes, but they should have told us sooner.”

Ryan and Pamela Murphy of Staten Island were planning to run their third and fourth New York City Marathon. But they soon decided to organize volunteers rather than run. Ryan Murphy said he was thrilled with the decision by Bloomberg and Road Runners.