Is it farther or further?
"female supporter of the cause of women's voting rights," 1906, from suffrage, with French fem. ending in vogue at the time. Earlier (without reference to sex) suffragist (1822) "advocate of extension of the political franchise in Britain," or, in the U.S., of voting rights for free blacks. Especially with reference to women after c.1885.
A suffragist. Today, the term suffragette is often considered demeaning.