We actually just began a discussion of "antichrists" and the biblical definition of "antichrist" on my recent blog post. Based on your question, and the questions of others, I would like to continue this discussion sooner, rather than later.

Before we can even begin to talk about whether or not Obama is the "antichrist," we need to understand the definition of "antichrist." The key passages to examine are: 1 John 2:18-26; 1 John 4:1-4; 2 John 7-11. I hope everyone who is interested in the answer to this question will examine these passages closely before my post on "Is Obama the Anti-Christ?" You can even run a search of your own on antichrist in the Bible by going to Bible.Logos.com and entering "antichrist" in the search bar. I also recommend going to WBSA.Logos.com and searching for "antichrist" in the search bar. WBSA stands for "What does the Bible Say About..."

You can check out what I have said so far on the topic here. Be sure to check out the comments, because that is where the questions about celebrity-style "antichrists" really begin.