After 3rd place finish in Iowa, Warren says she's built her campaign to go the distance

Sen. Elizabeth Warren, who once led in national polls as a top contender for the Democratic presidential nomination, is now trying to break out from the middle of the pack.

With just two days before the New Hampshire primary, the candidate who consistently says she "has a plan for that," said Sunday that she has no intention of quitting.

"Look, the way I see this is it's going to be a long campaign … we've built a campaign to go the distance," the Massachusetts senator said in an exclusive interview on ABC's "This Week."

Her interview Sunday comes on the heels of the eighth Democratic debate, where she took the stage with six other candidates to defend her place in the top tier of the race and contend with changing dynamics after the Iowa caucuses.

She is leaning on her potential neighboring-state advantage in hopes of a comeback in New Hampshire, telling crowds that being there feels like being with family. But she'll have to vie for that backyard boost with Sen. Bernie Sanders, I-Vt., who won the state in 2016 against Hillary Clinton and currently leads polls there.

And after Iowa, Warren is also seeing a challenge for front-runner status from former South Bend, Indiana, Mayor Pete Buttigieg.

She hopes to revamp enthusiasm by carving out a framed position as populist capitalist -- drawing a contrast between herself and Sanders -- a self-proclaimed Democratic socialist -- and something she steered away from at the debate.

"I am not -- I am a capitalist. I believe in markets," Warren told ABC News' Chief Anchor George Stephanopoulos Sunday. "But markets need rules. Markets without rules are theft. So it's a big part of what I'm running on. I want to see an America of opportunity. And that means we need a market economy -- that it's got to be a market economy that's fair and that everybody gets to play."

Yet Warren's stance still provides room to denounce big dollar influence in politics, allowing her to cite former New York City Mayor Mike Bloomberg by name.

"The way I see it right now is that we have a government that works great for a thinner and thinner slice at the top," Warren said, adding that meanwhile, every day Americans are "getting the short end of the stick. And what's the reason for that? It's corruption. It's a Washington that makes -- it's a bunch of billionaires that make big campaign contributions or reach in their own pockets, like Michael Bloomberg does," Warren said. "Billionaires, they may own more shoes than the rest of us, they may own more cars, they may own more houses, but they shouldn't own a bigger piece of our democracy."

Bloomberg and his vast fortune were absent from the New Hampshire debate stage, but Warren and several of her fellow candidates took the opportunity to slam his unorthodox candidacy, and used it to take veiled swipes at Buttigieg, over the influence of PAC money in his campaign.

Now, with the first-in-the-nation primary in her sights, Warren is harkening back to a founding campaign theme and what's become a signature rallying cry -- "Nevertheless, she persisted" -- and wedding that to a new tone of party unity in her rhetoric.

"There are a lot of folks who are going to talk about what's not winnable, what can't be done," Warren said to cheers Saturday in Manchester. "The way I look at this. I've been winning unwinnable fights pretty much all my life -- we persist and we win."