Obama is about to name a replacement for Justice Souter. There is some talk about picking a politician, maybe Salazar, Granholm, Klobuchar. There are some who are looking at demographics, eg. Judge Sotomayor.
All I have to say is be careful.
There are currently 4 votes on the court to overturn Roe v. Wade. There is no room for error.
Unless Obama has a very clear sense of a particular nominees judicial philosophy, Obama should not appoint them. That is the risk in picking a politician who has not written extensively on constitutional law. That may be a risk in picking an unknown judge.
Thomas and Scalia voted to overturn Roe v. Wade before. They had Rehnquist and were hoping to pick off Souter, Kennedy and O'Connor. The latter three wrote a concurring opinion that preserved but weakened Roe v. Wade.
Alito and Roberts are almost certain to vote to overturn Roe v. Wade. The right to choose hangs in the balance with the next pick.