What we saw with both Donald Trump and Marco Rubio, that their response, whenever you point to anything in their record, is just to yell, "Liar, liar, liar," and to get very personal and to make direct character attacks. And my approach, from the very beginning of this President's campaign, starting a year ago in 2015, is that I will not respond in kind. I do not intend to insult any of the candidates.

Over the last years we've seen the consequences of the Obama-Clinton foreign policy. Leading from behind is a disaster. We have abandoned and alienated our friends and allies, and our enemies are stronger. Radical Islam is on the rise, Iran's on the verge of acquiring a nuclear weapon, China is waging cyber warfare against America.

Democratic senators are more scared of their base than they are of the voters.

What is deemed "unlikeable" in Washington is actually standing up to Washington and saying no, saying "The emperor has no clothes," saying "We made promises to the people who elected us; let's do that."

A lot of my colleagues actually yell and curse at each other. I don't do that.

There is no doubt that if Donald [Trump] steamrolls through Super Tuesday, wins everywhere with big margins, that he may well be unstoppable. I don't think that will happen.

Donald Trump tweeted out to the world a quote allegedly from Senator Tom Coburn impugning my honesty. Within hours, Tom Coburn came out publicly and said, "That quote was an utter fabrication."