Complex sentence: The principal organization within this movement is Personhood USA, an umbrella group with a number of state-level affiliates which describes itself as a nonprofit Christian ministry and seeks to ban abortion, stem cell research and human cloning.
Split into simpler sentences: The principal organization within this movement is Personhood USA, an umbrella group with a number of state-level affiliates which describes itself as a nonprofit Christian ministry. They seek to ban abortion, stem cell research and human cloning.