WASHINGTON — Rep. Alexandria Ocasio-Cortez appeared for an hour-long town hall on MSNBC Friday evening to discuss her Green New Deal proposal and the issue of climate change but things got heated when an audience member called a former Republican congressman a "moron" during a debate.

While discussing the bill, former Rep. Bob Inglis, a Republican from South Carolina who lost his seat in Congress due to his ideas to combat climate change, said he didn't believe the Green New Deal could be done within one Congress (two years). He also voiced worries that holding a left-leaning event calling for attention to climate change could disenfranchise moderates or Republicans.

"I worry that what we do is if we have basically the mirror image of a Trump rally on climate change that we drive all the people away that could come our way and solve this thing now," Inglis said, adding that "You can't do it in a single congress —the entire Green New Deal. It is literally impossible."

He ended with a question, saying that if we take on climate change head-on if we could later come back to issues like universal basic income and healthcare, which have left Congress notoriously divided.

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His comments led to loud groans from the audience, many of whom appeared to be fans of Ocasio-Cortez, a Democrat. Some shouted "No!" One audience member shouted: "You moron!"

Ocasio-Cortez was readying to respond when she heard the audience member and stopped.

"Hey! Hey! Hey! That's unacceptable," Ocasio-Cortez said as she pointed her finger at the audience member. Then, looking back at Inglis, she added: "And that's the difference between me and Trump."

Ocasio-Cortez's aspirational proposal to confront climate change, co-sponsored by Sen. Ed Markey, D-Mass., was voted down this week in the Senate —and Democrats helped kill it.

No senator voted for it; 57 (including all Republicans and a handful of Democrats) voted against it; and the remaining 43 (all Democrats) voted "present" as a protest.

Congressional Democrats viewed the effort by Republicans – who ridicule the plan as socialist fantasy – to bring the ambitious plan to the floor as little more than a political ploy to divide Democrats rather than a serious effort to confront an impending planetary crisis.

Spurred by government reports warning of drastic consequences of climate change, Ocasio-Cortez and Markey unveiled the proposal in February.

It called not only for combating climate change by eliminating carbon emissions caused by fossil fuels and shifting the economy to one powered by renewable fuels but also prescribes a broad platform supporting free housing, medical coverage and higher education for all Americans.

GOP senators ridicule the plan because the Green New Deal's original talking points called for even further-reaching goals: a build-out of high-speed rail that would make carbon-emitting airplane travel obsolete; an end to dependence of nuclear power as well as fossil fuels; and the creation of "a sustainable, pollution and greenhouse gas free, food system" that would no longer rely on "farting cows."

Along with that, conservatives have pointed out that the proposal would have a price tag of billions.

Ocasio-Cortez took on those criticisms during Friday's town hall, telling host Chris Hayes that she expected conservatives to tear apart the proposal.

After watching a video compilation during the event showing Republicans attacking her and alleging the proposal was a threat to America, a socialist takeover and she was attempting to rid the nation of hamburgers and milkshakes, Ocasio-Cortez added that while she expected criticism, "I didn't expect them [Republicans] to make total fools of themselves."

Contributing: Ledyard King