DUBLIN — In what could be a historic vote, says USA Today, an estimated 3 million people across Ireland were expected to cast ballots Friday on whether to approve same-sex marriage, a change that appeared likely to pass despite opposition from the Roman Catholic church in this overwhelmingly Catholic nation. A "yes" vote to change Ireland's constitution to give gay couples the same rights as married heterosexual couples would mark the first victory for gay marriage by nationwide referendum. Eighteen other countries have legalized same-sex marriage through legislation or the courts, but not by a public vote.Read more on NewsOK.com