It is true that Oprah has some unbiblical ideas about salvation and homosexuality, but it doesn't mean they can never change. I think, we're better off praying for her enlightenment than criticizing her for her unbiblical beliefs. Many people who used to belong to false religions or were atheists...
Now, if you don't believe her, that's a different story. If you are a true Christian, you may sincerely ask God in prayer who to vote for. But you cannot label Ms Jacobs false prophet in this case. King Saul became King even though it was NOT THE WILL OF GOD, but it happened because the Israelite...
In all fairness, I don't think Mr Osteen is referring to unrepentant homosexuals who the Bible clearly states will not enter heaven (I Cor. 6:9-10).