A gay U.S. soldier who was booed during a Republican presidential debate in 2011 has joined the effort to overturn Ohio's ban on same-sex marriage.

Leaders of pro-gay-marriage group FreedomOhio said Friday that Columbus resident Stephen Snyder-Hill will help lead outreach efforts.

Snyder-Hill asked the GOP candidates in 2011 if they would reinstate the ban on openly gay troops. He was booed for the question, which he recorded while deployed in Iraq.

FreedomOhio wants to overturn the 2004 state constitutional amendment banning gay marriage. Supporters started collecting signatures last year to place their own constitutional amendment on the ballot by 2014.

The measure wouldn't require churches and other religious institutions to perform or recognize gay marriages.

The amendment banning gay marriage was supported by 62 percent of Ohio voters at the time.