A national group of prominent GOP donors that supports gay marriage is pouring new money into lobbying efforts to persuade Republican lawmakers to make it legal.

American Unity PAC was formed last year to lend financial support to Republicans who bucked the party’s longstanding opposition to gay marriage. Its founders are launching a new lobbying organization, American Unity Fund, and have spent more than $250,000 in Minnesota, where the legislature could vote on the issue as early as next week.

The group has spent $500,000 since last month, including efforts in Rhode Island, Delaware, Indiana, West Virginia and Utah.

Billionaire hedge fund manager and Republican donor Paul Singer launched American Unity PAC. The lobbying effort is the next phase as the push for gay marriage spreads to more states, spokesman Jeff Cook-McCormac said.

“What you have is this network of influential Republicans who really want to see the party embrace the freedom to marry, and believe it’s not only the right thing for the country but also good politics,” Cook-McCormac said.

Part of American Unity ’s original mission was to spend money on behalf of Republican gay marriage supporters. Many GOP lawmakers have faced primary challenges funded in part by anti-gay marriage groups such as the National Organization for Marriage, which argue that the lawmakers have betrayed the party’s core principles.

There are also plans to lobby federal lawmakers on gay rights issues.

— Associated Press