Teddy "The Swimmer" Kennedy can claim to be against abortion personally, but he cannot legally prevent it nor vote against it.
Ronald W. Reagan supported the Human Life bill, the Respect Human Life Act, as well as worked toward an Amendment ENDING abortion in every state. Who of the three is working to end abortion, and whose positions would extend/protect it?
"No amendment shall be made to the Constitution which will authorize or give to Congress the power to abolish or interfere, within any State, with the domestic institutions thereof, including that of persons held to labor or service by the laws of said State."
All that says is that it's a matter for the states. Nothing in it says, "slavery shall be permanent forever and can never be outlawed anywhere." It says the federal government won't interfere with it.