The National Organization for Marriage (NOM), the nation's largest group opposed to marriage equality, on Wednesday endorsed Texas Senator Ted Cruz for president.

Citing the many Republican presidential candidates who oppose such unions, NOM said that the decision to endorse Cruz was “a very difficult one."

“There are many tremendous candidates remaining who have made support for marriage a pillar of their careers in public service, including Sen. Rick Santorum, Gov. Mike Huckabee, Dr. Ben Carson and Sen. Marco Rubio,” NOM said in a press release.

The group said that it had decided to endorse “a proven champion.”

“Sen. Ted Cruz is a proven champion for marriage and religious freedom and someone we can absolutely count on to fight to restore marriage to our nation's law and defend the religious liberty of the tens of millions of Americans who believe that marriage is the union of one man and one woman, Sen. Cruz has only not only signed NOM's presidential marriage pledge committing to take specific actions as president, but he has personally authored the pending federal marriage amendment to restore the right of states to define marriage as one man/one woman.”

“We believe [that Cruz] has the best chance of uniting conservatives and going on to win the nomination,” the group added.