A century and a half after President Abraham Lincoln designated Thanksgiving a national holiday, fans of the woman who lobbied for the commemoration are hoping she will gain fresh recognition for her many other accomplishments.

A new memorial to Sarah Josepha Hale in her hometown of Newport, N.H., might help. The memorial, dedicated before about 200 people over the weekend, was the brainchild of an anonymous donor who financed the project.

The work by Finnish sculptor Jari Mannisto, tucked into a small park near the town’s Richards Free Library, showcases Hale’s role as a writer, magazine editor and fundraiser for Boston’s Bunker Hill Monument—not to mention scribe of the poem that became the nursery rhyme “Mary Had a Little Lamb.”

Despite Hale’s impressive résumé, “she is off the radar, honestly,” said Patricia Okker, an English professor at the University of Missouri who wrote a book about her. “And when she is remembered, it’s almost always because of Thanksgiving, which is an interesting part of her career, but her career was so enormous.”

Born in 1788, Hale lived nine decades. She spent much of her life editing women’s magazines, including the widely read “Godey’s Lady’s Book,” which featured writers including Nathaniel Hawthorne and Harriet Beecher Stowe. Hale championed women’s education and wrote an antislavery novel in the 1820s.

She spent many years pushing to elevate Thanksgiving to the federal level to standardize the holiday, celebrated by various states at different times. Hale wrote Lincoln in September 1863, prodding him on, and he issued a proclamation soon thereafter.

But Hale also had views that are harder to digest in modern times and may have diminished her reputation, supporters say. Namely, despite her strong advocacy for women, she didn’t support their right to vote.

“My theory is that in the resurgence of feminist history, Sarah Hale was kind of ignored because she was not a suffragette,” said Andrea Thorpe, the Newport library’s director.

The town’s memorial to Hale features a cornucopia and items representing key parts of her life, including arms with broken shackles to highlight her antislavery views. A bronze bust of Hale sits atop a tall, black granite pillar, representing the black garb she wore during her long widowhood, according to the library. Her husband, a lawyer, died when she was in her 30s, leaving her to support their five children.

In Newport, at least, Hale remains a star, even though she spent most of her life elsewhere to pursue her editing career. Newport’s website calls her the town’s “most famous native,” and a vaudeville star tried raising money in the 1930s to create a statue of Mary’s lamb for the town common, Ms. Thorpe said. Though the fundraising came up short, the money was eventually used to fund an annual literary award in Hale’s name that the library has handed out since 1956.

She also had a patriotic streak fueled by her father’s role in the Revolutionary War, according to Mary Lou McGuire, the library’s archivist.

“She’s sort of an unsung heroine,” said Carl Zellner, the 78-year-old historian at the Charlestown Historical Society. That Boston neighborhood is home to the Bunker Hill Monument, which commemorates the first major battle of the Revolutionary War.

“I think she’s very worthy of commemoration and recognition, and for her it just hasn’t happened,” Mr. Zellner said.

MJ Lewis, a speech and communications instructor at the University of Hawaii, Windward campus who has studied Hale, has long wondered about her lack of support for women’s voting rights. She suspects that Louis Godey, founder of “Godey’s Lady’s Book” and Hale’s longtime collaborator, preferred to avoid politics.

But Dr. Lewis, who is raising money for a documentary on Hale, said she was also a complex woman in a changing time: “She was kind of caught between the old Victorian mentality and the new, emerging feminism.”

Write to Jon Kamp at jon.kamp@wsj.com