Here are some excellent comments on Romans 9 from Dr. William Lane Craig. (This is an excerpt from Dr. Craig’s answer to a question from an atheist, taken from http://www.reasonablefaith.org/site/News2?page=NewsArticle&id=6675.)
[L]et’s talk about Paul’s doctrine of election in Romans. I want to share with you a perspective on Paul’s teaching that I think you’ll find very illuminating and encouraging. Typically, as a result of Reformed theology, we have a tendency to read Paul as narrowing down the scope of God’s election to the very select few, and those not so chosen can’t complain if God in His sovereignty overlooks them. I think this is a fundamental misreading of the chapter which makes very little sense in the context of Paul’s letter.