Bernie Sanders has begun to break away from the rest of the Democratic primary field. He is leading in an average of national polls, and currently tops the delegate count.

At CPAC this week, Sanders faced attacks from speakers, and attendees openly worried about his candidacy -- a sign that some conservatives believe that Sanders may be the eventual Democratic nominee.

The rhetoric plays into President Donald Trump and his supporters' strategy to tie the 2020 Democrats to socialism, a term they believe has negative connotations for voters.

It also provides a potential preview of the attacks Trump and his followers would use on Sanders if he won the nomination.

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NATIONAL HARBOR, Md - The name on everybody's lips at the Conservative Political Action Conference (CPAC) yesterday was…Bernie.

America's annual gathering of conservatives in Maryland featured speakers who attacked him from the main stage as a "dictator apologist," "comrade", and a "Marxist." Attendees worried openly about his candidacy. Crowds booed him. In fact, the subtitle of the entire conference was "America versus Socialism."

President Donald Trump and his supporters in the Republican Party have attempted to paint the 2020 Democrats as "socialists", a term they see as a negative term with Cold War-era connotations that will frighten voters. The hostility directed towards Sanders at CPAC on Thursday previewed likely lines of criticism from Republicans if he were to win the Democratic nomination — and the amount of attention he received indicated that conservatives now see him as a likely opponent to Trump in November.

The attacks come as Sanders begins to break away from his rivals in the primary. Sanders effectively tied former mayor Pete Buttigieg in the Iowa Cacuses and won both the New Hampshire primary and Nevada caucuses. He currently leads the national delegate race, and FiveThirtyEight's national polling average shows Sanders currently leading the rest of the Democratic field.

A Fox News poll of 1,000 registered voters conducted from February 23-26 found Sanders leading with 31% of support, while former vice president Joe Biden came in second with 18%. The poll also found 65% of voters believed Sanders could beat Trump in November, ahead of Bloomberg (57%) and Biden (56%).

Other Democratic candidates were mentioned at CPAC — but none came up, or were excorciated — as much as Sanders.

Nobody inveighed harder against Sanders than Charlie Kirk, the founder of Turning Point USA and chairman of college group Students for Trump. He described Sanders in a speech Thursday morning as a "Bolshevik" and a "Marxist."

"He could win," he said. "I want every conservative activist to get their laughs out of the way…and then get deadly serious."

Kirk claimed that college students were being indoctrinated with socialist ideas, making Sanders a dangerous candidate.

"We have a dictator apologist who is the frontrunner of the Democratic Party," Kirk said. He said that "we beat communism in Europe but then communism came to our college campuses."

When Diamond and Silk, a pair of black conservative media personalities with a popular Facebook presence, skewered the Democratic candidates one by one, it was Sanders' names that drew the most boos from the crowd — and their insults that elicited the most applause.

"When I look at Bernie Sanders and his socialistic ideas it reminds me of the initials of his first name, Silk," said Diamond, whose full name is Lynnette Hardaway. "Straight B.S."

The crowd got the message.

"Unfortunately Bernie Sanders has such a footing because the kids have been brainwashed at colleges to believe socialism is a good thing," said Rene Campbell, 57, who had just listened to Kirk's speech and believed Sanders would be the 2020 nominee.

"Once it happens, it'll be too late, we'll be in the thick of it, it'll be too late to get out," Campbell said. "It's so twisted right now."

Sean Hyadick, a student at the conservative Hillstone College in Michigan and part-time butcher, said that he thought the Democratic nominee would be "Sanders, partially due to name recognition. I think he has more traction with a liberal student base on most college campuses."

"He'd be a more difficult opponent to beat than Bloomberg, per se," Hyadick added.

"Bernie Sanders, he's crazy," said another CPAC attendee, Princess Kvevor, 27. "I'm surprised people are even supporting him considering some of his ideas."

Democratic socialism and "socialism" are related but distinct ideologies. But Republicans are trying to muddle the waters with voters, and link Democratic socialism with authoritarian regimes like the former Soviet Union or Venezuela.

There are different meanings, interpretations and economic theories of socialism. It can advocate for "collective or governmental ownership and administration of the means of production and distribution of goods," according to Merriam-Webster. In other interpretations, the "means of production are owned and controlled by the state."

Democratic socialists, like Sanders and Ocasio-Cortez, however, believe that the government should provide some services to the public, but also support Democratic principals. Sanders has called for tuition-free college and Medicare-for-All on the campaign trail.

"At the root of our socialism is a profound commitment to democracy, as means and end," the Democratic Socialists of America write on their website.

But Trump and his allies have tried to tie Democratic Socialists to more authoritarian manifestations of the political ideology and versions of socialism, as Insider's John Haltiwanger reported.

In his State of the Union address in 2019, Trump invoked the turmoil Venezuela and "the brutality of the Maduro regime, whose socialist policies have turned that nation from being the wealthiest in South America into a state of abject poverty and despair."

That thread continued at CPAC this week, where there were also attempts to paint Sanders as a communist, another word with highly negative connotations in U.S. politics as a result of decades-long struggles with the Soviet Union during the Cold War.

Speakers at the conference only see one antidote to Sanders: Trump.

"The best way we can make sure Bernie never gets his agenda through is to make sure we have four more years of President Donald Trump," Tennessee Senator Marsha Blackburn said on Thursday.

On Friday morning, former Fox News personality and Trump campaign advisor Kimberly Guilfoyle referred to Sanders as "Comrade Bernie" and warned the Democrats were "one step closer to anointing a socialist to lead their party."

"Let 'em run," Guilfoyle said. "Nothing can stop the Trump train."

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Trump's latest line of attack against 2020 Democrats is to tie them to socialism