This is a great site:
http://winningargument.blogspot.com/Here's a sample:
Ex-felons should be allowed to vote.Why you're right:1. The laws are a relic of a time when states sought to prevent blacks from voting. Because blacks are convicted of crimes at disproportionate rates, they are still achieving that effect. In Florida and Virginia, for example, 16% of the black adult population is ineligible to vote.
2. It diminishes the right to vote. Granting the right to vote only if someone meets certain character requirements makes voting less of a right and more of a privilege. This threatens to undermine one of the primary goals of the civil rights movement.
3. Granting ex-felons the right to vote enhances the rehabilitative goal of sentencing. Those who have "paid their debt to society" they should be welcomed back into the community fully. A primary goal of the criminal justice system should be "is to encourage offenders to become less antisocial." Therefore, it is in society’s interest to engage offenders in productive relationships with the community," like voting.
Why they're wrong:Opponents of voting rights for ex-felons stress the importance of being "tough on crime." But there is no evidence to suggest that someone who is ready to ignore the threat of incarceration will be swayed by the prospect of losing their right to vote. Anti-crime policy should focus on deterring crime, not branding people as criminals.