From the transcript in response to a question on immigration reform:

So when I hear the opposition to immigration reform, I just run through the list of things that are concerned about, I look at what the Senate bill does, and I say to myself, you know what, the Senate bill actually improves the situation on every issue that they say they’re concerned about.

Now, what they may argue is it doesn’t solve the problem a hundred percent. I don’t know a law that solves a problem a hundred percent. Social Security lifted millions of seniors out of poverty, but there are still some poor seniors. The Civil Rights Act and the Voting Rights Act drastically reduced discrimination in America, but there’s still discrimination. That doesn’t make them bad laws. It just means that there are very few human problems that are a hundred percent solvable.