What is a "Believer"?

The application form asked what I would answer if God asked me why I should be permitted to enter Heaven.  After I kicked back at that question in my mind, (because the first thought was, "that's absurd"), I realized that it was an effective way to extract the desired information from someone.

The answer that came to mind is actually a good tool to simply explain to someone who is unaware of God's ways with man:  God says that the blood of Jesus Christ cleanses me from ALL sin. I believe that, and He accounts or credits it to me for righteousness.

That's simple.  I believe Him and I'm righteous. 

Are you a believer?