Interview with Martha Raddatz of ABC News' "This Week"

RADDATZ: Bernie Sanders is hard at work on the campaign trail this holiday weekend. And he joins me this morning from New Hampshire. Happy new year, Senator Sanders.

We noticed that today is the 25th anniversary of your first day in Congress. Twenty five years, what do you say to critics who say the country needs a president from outside Washington and not a career politician?

SANDERS: Well, what I say is if you study my record, I'm not exactly a career politician. Martha, during my tenure in the Congress, I have taken on virtually every powerful special interest from Wall Street to the insurance companies to the pharmaceutical industry to the military- industrial complex.

What my campaign is about is standing up to the billionaire class today, and making certain that we do not continue to see the decline of the American middle class, where people are working longer hours for lower wages and almost all new income and wealth is going to the top 1 percent. That is the issue that I find that the American people are most concerned about, the decline of the middle class, massive income and wealth inequality, and a corrupt campaign finance system.

RADDATZ: Well, let me take you back to 1990 on election night. This is what you said. "We need a mass movement of tens of millions of people prepared to say that we want national health care, that we want the millionaires and multi-national corporations who are not paying their fair share, to pay their fair share."

That sounds an awful lot like Bernie Sanders 2015, but you haven't really been able to create that mass movement. How can we imagine that you'll do it now?

SANDERS: Well, Martha, we're doing pretty well. You know, I started this campaign at 3 percent in the polls. There were some polls that had me out recently at 39 percent. Come to my meetings. They're huge all over the United States of America.

And what we are seeing is mass dissatisfaction on the part of the middle class. We're seeing people who are really upset that they can't afford to send their kids to college. They can't afford childcare. The rich are getting richer; almost everybody else is getting poorer. And what people are saying is, you know, it's absurd. That with massive income...

RADDATZ: Let me turn to Iowa.

SANDERS: ...and wealth inequality...

RADDATZ: Let me turn to Iowa, Senator Sanders. This is what you recently said at a campaign stop.

[begin video clip]

SANDERS: Let me tell you a secret, don't tell anybody. I don't want to get Secretary Clinton nervous. [cheers] I think we're going to win here in Iowa. [cheers]

[end video clip]

RADDATZ: I don't know how nervous Secretary Clinton is about that. She has consistently led in the polls in Iowa through the latter part of 2015. What can you possibly do to try to stop that momentum in just four weeks?

SANDERS: Martha, should have been with us in our last trips to Iowa. The turnouts that we're seeing in big towns and in small towns are extraordinary. The enthusiasm is very, very strong. I think that people are tired of establishment politics and establishment economics. And they are also tired of a corrupt campaign finance system in super PACs that allows billionaires to purchase elections. That's not what the American people want.

And one of the manifestations of that is the kind of incredible fundraising that we have been doing in terms of small, individual donations. We have 2.5 million small, individual contribution-style campaign. That is more than any campaign in the history of the United States of America, and I think that speaks to the enthusiasm and support that we're getting at the grassroots.

RADDATZ: Hillary Clinton has Bill Clinton joining her on the campaign trail there in New Hampshire this week. Donald Trump and Washington Post columnist Ruth Marcus think Bill Clinton's sexual history is fair game. Do you?

SANDERS: No, I don't. I think, you know, we have enormous problems facing this country and I think we got more things to worry about than Bill Clinton's sexual life. I think -- interestingly enough, maybe Donald Trump might want to focus attention on climate change, understand that climate change is not a hoax, as he believes that it is, that maybe Donald Trump should understand that we should raise the minimum wage in this country, which he opposes, and maybe we should not be giving huge tax breaks to fellow billionaires like Donald Trump.

So I think maybe he should focus on those things.

RADDATZ: You have had some very harsh words for Donald Trump recently and you said you wanted to stay away from personal attacks...

SANDERS: Yes.

RADDATZ: ...in this campaign.

SANDERS: Right.

RADDATZ: Some of the things you've said, like calling him a pathological liar, have been pretty personal.

SANDERS: Yes. The truth is I do not get engaged in personal attacks, but Trump really is over the edge. He has attacked me very ferociously and has called me a liar because I point that out, that nobody else has seen on television thousands of Muslims celebrating the destruction of the Twin Towers.

Time after time, this guy just comes up with things off the top of his head that are lies. And somebody has got to say that he is a pathological liar.

RADDATZ: Senator Sanders, President Obama is reportedly considering executive action that would require unlicensed gun dealers to get licensed by the ATF and conduct background checks on potential buyers. Recent polling shows three in four Americans thinks it's important that there be bipartisan consensus before implementing gun control. Is an executive action that circumvents Congress the right way to do it?

SANDERS: Well, I wish that we could get bipartisan action on gun safety legislation. I think the American people have been horrified by the mass shootings we've seen over the last couple of years. What I think we need to do, among many other things, is do away with the so- called gun show loophole where people are -- do not have to go through the instant background check.

Martha, there is a wide consensus, overwhelming majority of the American people believe we should expand and strengthen the instant background checks so that people who should not have guns, are i.e. criminals or people with mental issues, mental health issues, should not guns. I think that's what the president is trying to do and I think that will be the right thing to do.

RADDATZ: And very quickly, Senator Sanders, on the campaign trail last week, you said that the retaking of Ramadi in Iraq is a model for destroying ISIS and that training of Iraqi troops may have turned things around. Eighty percent of the reason Ramadi is falling is because of coalition air strikes, though. That's what you think should continue?

SANDERS: Right. I think it has to be Muslim troops on the ground who are fighting for the soul of Islam, supported by U.S., French, U.K., German, other major powers, and using our air superiority.

RADDATZ: Might be very difficult to get those ground troops, but thank you very much, Senator Sanders.