Democratic presidential candidate Bernie Sanders is defending himself against recent claims by Hillary Clinton that his campaign was "lying" about donations she has received from the fossil fuel industry.

"If people receive money from lobbyists of the industry, I think you're receiving money from the industry," Sanders told "CBS This Morning" in an interview early Friday.

On Thursday, a frustrated Clinton was confronted by a Greenpeace activist while campaigning in New York. When asked whether she would disavow any "fossil fuel money in the future," Clinton responded that she does not receive contributions from fossil fuel companies.

She added: "I'm so sick of the Sanders campaign lying about this, I'm sick of it!"

But in his Friday interview, Sanders cited a Greenpeace study that said Clinton received over $4 million from the fossil fuel industry, with individual contributions from over 50 lobbyists.

"CBS This Morning" host Charlie Rose pointed out that according to another source, FactCheck.org, Clinton's campaign has not received any direct contributions from any corporation, including oil and gas companies.

"There's a difference - if you are a lobby from the fossil fuel industry, and there are 50 of you and you make a contribution, that to me, Charlie, is a contribution from the fossil fuel industry," Sanders said. "That's different from saying you get it from Exxon Mobil."

The Democratic candidate emphasized that these contributions were still from "lobbyists who represent the oil and gas industry."

With more nominating contests at stake this month -- including large delegate prizes like Wisconsin and New York -- Sanders also outlined his path forward in the Democratic race.

"We have won six out of the last seven caucuses," Sanders said. "In every instance, we've won by landslide victories. We're fighting hard in Wisconsin. I think we've got a shot to win here in New York state."

Later, Sanders said he didn't want to "speculate" about the outcomes of those primary elections, but added that "when voter turnout is high... then we win."

If, however, "the voter turnout is low -- in Wisconsin, New York state -- you know what, we'll likely not win," he said.

Against fellow New Yorker and current GOP front-runner Donald Trump, Brooklyn's native son said he would fare better in that general election matchup than Clinton -- a prediction supported by recent polling.

"I think more and more Democrats are looking at Bernie Sanders as the candidate who can best defeat Trump or some other Republican candidate," he said.

When asked if he would support Clinton if she won the nomination, however, Sanders declined to answer.

"I obviously can't speak for millions of supporters, individual people," Sanders said. "What I can tell you is I think it would be an absolute disaster for this country if we had a Donald Trump as president of the United States and I will do everything I can to prevent that."

Pressed again if that meant backing the former secretary of state, Sanders replied: "Well, I'm sure that when Hillary Clinton announces that she'll be supporting me, we'll go forward together."