This is a rush transcript from "Special Report," October 13, 2015. This copy may not be in its final form and may be updated.

SHANNON BREAM: Tonight's Democratic presidential debate in Las Vegas will be the first time many Americans get to hear Vermont Senator Bernie Sanders for a significant length of time. Sanders has shocked the political world this year, turning a small grassroots effort into a significant national campaign. My colleague Bret Baier, on assignment tonight, profiles Sanders in our ‘Presidential Contenders Series.’

(BEGIN VIDEOTAPE)

BRET BAIER, FOX NEWS CHIEF POLITICAL ANCHOR: A year ago, no one predicted, no one could predict the huge crowds and the surge of popularity for 74-year-old Senator Bernie Sanders.

SEN. BERNIE SANDERS, I-VT., DEMOCRATIC PRESIDENTIAL CANDIDATE: Whoa. Unbelievable. This is an unbelievable turnout.

BAIER: Even he's been blown away by it.

SANDERS: What a huge crowd.

BAIER: The independent senator from Vermont caucuses with the Democrats in the Senate and is a committed Democratic socialist. And he's not afraid for everybody to know it.

CHUCK TODD, NBC NEWS HOST: Are you a capitalist?

BAIER: No, I'm a Democratic socialist. What I mean is I've been elected as an Independent throughout my political career. I'm running now in the Democratic nomination process. And will support, I hope to win, I expect to win.

BAIER: Sanders officially launched his campaign from Vermont in May.

SANDERS: I am proud to announce my candidacy for president of the United States of America.

BAIER: Sanders jumped quickly in the polls especially in early states and his favorability tripled. For third quarter fundraising, his campaign reported $26 million -- just $2 million less than Hillary Clinton. But Sanders is spending a lot less. Most of Sanders' fundraising comes from small donations. His campaign has only held a handful of traditional fundraisers.

UNIDENTIFIED MALE: I think he's not an establishment candidate. And it's refreshing.

UNIDENTIFIED FEMALE: Everything that he says is spot-on. I was a Hillary supporter for so long. But I really like what Bernie says.

UNIDENTIFIED MALE: It's time for a guy that is for the people. I think Bernie is for the people.

BAIER: And that's Sanders' pitch on the stump -- a man who has been around the block, fighting for poor and working-class Americans.

SANDERS: The intentions that I outline for you are more progressive than anyone else's.

BAIER: Among other things, Sanders campaigns on more jobs, a higher minimum wage, free college and universal health care.

SANDERS: This is the wealthiest country in the history of the world.
We can and must do better by working people.

We have got to raise the minimum wage to a living wage, $15 an hour over the next few years.

We should have pay equity for women workers.

I have introduced legislation and will fight to make happen as president, to see that every public college and university in America is tuition-free.

The United States of America remains the only major country on earth that does not guarantee health care to all people as a right and that is why I strongly support our country moving toward a Medicare for all single-payer program.

BAIER: That all sounds good on the campaign trail. But the "Wall Street Journal" recently added up the price tag of all of Sanders' new and expanding programs. $15 trillion pays for Medicare for all, a single-payer health care plan; $1.2 trillion for increasing benefits and shoring up social security; $1 trillion for an infrastructure program, rebuilding roads, bridges and airports; $750 billion for tuition-free public schools and more favorable refinancing of student debt; $319 billion for paid family leave and medical leave; $29 billion to prevent companies from cutting pensions, $5.5 billion to create one million jobs for disadvantaged youth, and a child care pre-k proposal that's on the way.

Still to come, all of that adds up to $18 trillion of new spending over a decade. That's the largest peace time expansion of government in modern American history, something Sanders responded to directly.

BERNIE SANDERS, D, PRESIDENTIAL CANDIDATE: It's really not a fair analysis. Of that $18 trillion, $15 trillion has to do with health care. And the view, my view, and my position that we have got to move toward a Medicare for all single payer system. What they forgot to tell the American people is that whether you like single payer or not, the evidence is overwhelming that it will be less expensive than the current dysfunctional system that we now have. They forgot to take that into consideration. They forgot to tell the American people they would not be paying private health insurance costs at all. So I think that was disingenuous on the part of the "Wall Street Journal."

But, having said that, do I believe that we should create millions of jobs by rebuilding our crumbling infrastructure? Yes, we pay for that. Do I believe that we should make public colleges and universities tuition- free? Yes. And we pay for that by imposing a tax on Wall Street speculation. So I think we are going to spend a lot of money. But we're going to create a lot of jobs, and we are going to pay for everything that we are proposing.

BAIER: How Sanders exactly plans to do that is not yet clear, although his campaign says his proposed tax increases could bring in about $6.5 trillion over 10 years. Sanders' political career began in 1981 when he was elected for the first of four terms as the mayor of Burlington, Vermont.

LARRY SABATO, UNIVERSITY OF VIRGINIA: He barely won after having lost a series of races. But he was popular there. They saw him as a down-to- earth individual who did try to do what people wanted done in that town.

BAIER: His career in Washington began in 1990. Sanders went on to serve 16 years in the House before being elected to the U.S. Senate in 2006.

SANDERS: I believe that destiny has suggested that this small state of Vermont is in fact going to lead America in a very different direction.

BAIER: Now in his second term, Sanders is the ranking member of the Senate Budget Committee. He previously served as chairman of the Veteran Affairs Committee, helping to pass legislation in 2014 reforming the V.A.
health care system. At 74-years-old, he's the longest-serving independent in United States congressional history. And yet, on the trail, he's not perceived as a career politician.

SABATO: The other great strength Bernie Sanders has, is the ability to communicate effectively and to tell people precisely what he thinks, whether they like it or not. There seems to be a demand in the country for the un-politician, for someone who comes at them straight.

BAIER: Sanders promises to run a campaign that's free of negativity, and even travelled to conservative Liberty University to discuss differences in opinion.

SANDERS: I came here today because I believe from the bottom of my heart that it is vitally important for those of us who hold different views to be able to engage in a civil discourse.

(APPLAUSE)

BAIER: Sanders is not hesitant to contrast himself with his chief rival, Hillary Clinton, especially on key issues for progressives, like the environment and trade.

SANDERS: From day one I opposed the Keystone pipeline because I believe that if you're serious about climate change you don't encourage the excavation and transportation of very dirty oil. That was my view from day one. TPP -- I believe that our trade policy is going way back when. I voted against NAFTA, CAFTA, the PNTR with China.

BAIER: On foreign policy, asked about the way forward in Syria, Sanders is also quick to remind people of his contrast with Hillary Clinton on an important U.S. Senate vote.

SANDERS: I voted against the war in Iraq. And I believe that was the right vote because this war clearly, that war has led to the destabilization of the situation right now. It is wrong to ask the United States of America alone, our armed forces, our taxpayers to put that country back together again. You need a regional force of people who are prepared to take on ISIS and destroy that barbaric organization.

BAIER: The biggest question for Sanders is whether he can unite the various factions of the Democratic Party, including minority voters, to out-progressive Hillary Clinton from the left in order to win the nomination, and then convince independents who don't lean left that he's the man for the Oval Office in a general election.

SABATO: In Democratic circles, Bernie Sanders lass a nickname. The nickname is George McGovern. George McGovern in 1972 carried Massachusetts and the District of Columbia. He lost 49 states. When you come right down to it, it's very, very difficult to imagine Bernie Sanders being elected president of the United States.

(END VIDEOTAPE)

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