WASHINGTON — Potential presidential candidate Newt Gingrich quietly lined up $150,000 to help defeat Iowa justices who threw out a ban on same-sex marriage, routing the money to conservative groups through an aide’s political committee.

Gingrich, the former U.S. House speaker who has aggressively courted the conservatives who dominate Iowa’s lead-off presidential caucuses, raised the money for the political arm of Restoring American Leadership, also known as ReAL.

That group then passed $125,000 to American Family Association Action and an additional $25,000 to the Iowa Christian Alliance — two of the groups that spent millions before last November’s elections that removed three of the state’s seven Supreme Court justices. The court had unanimously decided a state law restricting marriage to a man and a woman violated Iowa’s Constitution.

The financial transfers, which appear to comply with campaign finance laws, were part of a steady flow of cash into Iowa from conservative groups such as the National Organization for Marriage and the Family Research Council.

The spending comes as Gingrich is seeking to make allies among social conservatives who drive the caucuses, though some voters might question whether an outsider should be raising money for a contentious ideological fight confined to one state.

Presidential candidates regularly raise money for state legislators as a way to ingratiate themselves. But Gingrich’s behind-the-scenes role in one of the nation’s most contentious ballot measures last year was unusual. There are a number of companies and nonprofits that Gingrich founded or lent his credibility to after his resignation from Congress.

Gingrich’s longtime spokesman Rick Tyler serves as chairman of ReAL, which operates with the goal of preserving “America’s Judeo-Christian heritage by defending and promoting the three pillars of American civilization: freedom, faith and free markets.” Gingrich has no legal role in the operations, although he carries the title of honorary chairman and lends his name to fundraising. The group’s website, in turn, promotes Gingrich’s books, television appearances and films.

Gingrich’s involvement with the plan to oust the justices started last year when he met privately with hundreds of pastors and their spouses. The effort seemed tailored for social conservatives, whose support Gingrich will need if he is to mount a credible campaign in Iowa and who may hesitate to back the thrice-married candidate.