Among them are Meg Whitman, who supported Proposition 8 when she ran for California governor; Representatives Ileana Ros-Lehtinen of Florida and Richard Hanna of New York; Stephen J. Hadley, a Bush national security adviser; Carlos Gutierrez, a commerce secretary to Mr. Bush; James B. Comey, a top Bush Justice Department official; David A. Stockman, President Ronald Reagan’s first budget director; and Deborah Pryce, a former member of the House Republican leadership from Ohio who is retired from Congress.
Ms. Pryce said Monday: “Like a lot of the country, my views have evolved on this from the first day I set foot in Congress. I think it’s just the right thing, and I think it’s on solid legal footing, too.”
Jon M. Huntsman Jr., the former Utah governor, who favored civil unions but opposed same-sex marriage during his 2012 presidential bid, also signed. Last week, Mr. Huntsman announced his new position in an article titled “Marriage Equality Is a Conservative Cause,” a sign that the 2016 Republican presidential candidates could be divided on the issue for the first time.