Sen. Bernie Sanders (I-VT) on Wednesday delivered a full-throated defense and definition of “democratic socialism” as the only means to defeating President Trump and bringing about change in the United States.

“We must recognize that in the 21st century, in the wealthiest country in the history of the world, economic rights are human rights,” he explained. “This is what I mean by democratic socialism.”

“We must take the next step forward and guarantee every man, woman and child in our country basic economic rights—the right to quality health care, the right to as much education as one needs to succeed in our society, the right to a decent job, the right to affordable housing, the right to a secure retirement and the right to live in a clean environment,” Sanders said at George Washington University, further describing his vision as a completion of the “unfinished business” of President Franklin Delano Roosevelt’s New Deal.

It’s far from news that the independent senator from Vermont, whose 2016 presidential run encouraged a boon in membership for the Democratic Socialists of America, espouses such views. But the delivery of this candidacy-defining speech comes at a moment in which Republicans have used the specter of the word “socialism” to define Democratic candidates as extremists.

Meanwhile, centrist Democrats have raised concerns that tarring the word “socialism” would be an effective attack and a means by which Trump could hold onto the White House in 2020. And despite a broader leftward lurch of the Democratic primary field, there are no candidates who have effusively espoused a “democratic socialist” vision in such terms as Sanders did Wednesday.

As such, some of Sanders’ fellow candidates have openly warned against embracing democratic socialism.

“We must present a bold vision for the future, but we also must acknowledge that the most effective attack the Republicans can level against us is ‘socialism,’” Former Colorado Governor John Hickenlooper said during a speech Sunday at the Iowa Democratic Hall of Fame dinner. “Now, that does not mean that Democrats should shy away from big progressive goals. Far from it. A pragmatist doesn’t say no to big ideas, they figure out how to get them done.”

Sanders and his allies characterize his views as far from radical—particularly in the context of expanding on broadly popular social programs instituted by FDR. They point to the fact that his policies of Medicare-for-All, tuition-free college, and a $15 federal minimum wage have become mainstream in the 2020 Democratic campaign; that they poll well with voters; and that Sanders defeats Trump in current head-to-heads nationally and in the Midwest.

Invoking Martin Luther King Jr., President Roosevelt, and past instances in which Republicans have labeled Democrats as “socialists,” Sanders aggressively confronted the label head-on with an acknowledgment that he would be attacked for it.

“Let me be clear,” he said. “I do understand that I and other progressives will face massive attacks from those who attempt to use the word ‘socialism’ as a slur. But I should also tell you that I have faced and overcome these attacks for decades—and I am not the only one.”

The speech also served as a reminder of Sanders’ unique position in the current Democratic field, as he has found himself wedged in recent polls between former Vice President Joe Biden and one of his closest Senate colleagues, Sen. Elizabeth Warren (D-MA).

Sanders has drawn contrasts with Biden—by name and not—characterizing his candidacy as one beset by middle-ground approaches that run the risk of failing to excite Democratic voters.

“I understand that there are some well-intentioned Democrats and candidates who believe that the best way forward is a middle ground strategy that antagonizes no one, that stands out to nobody and that changes nothing,” Sanders said Sunday in Iowa, avoiding naming any particular candidates. “In my view, that approach is not just bad public policy,” he said, “but it is a failed political strategy that I feel could end up with the reelection of Donald Trump.”

On Wednesday, Sanders also assailed Trump and Wall Street as being hypocritical about democratic socialism, specifically pointing to the 2008 bailouts.

“In 2008, after their greed, recklessness and illegal behavior created the worst financial disaster since the Great Depression—with millions of Americans losing their jobs, their homes and their life savings—Wall Street's religious adherence to unfettered capitalism suddenly came to an end,” he said. “Overnight, Wall Street became big government socialists and begged for the largest federal bailout in American history—over one trillion from the Treasury and even more from the Fed.”

Nearly four years ago, Sanders delivered a speech about democratic socialism during his first run for the presidency, helping define such views for a broader audience that was also just getting acquainted with the candidate himself. Since then, DSA has ballooned to at least 56,000 nationwide members, won state legislative races around the country, and elected two members to Congress including Rep. Alexandria Ocasio-Cortez (D-NY).

On Wednesday, Sanders’ furthered his vision by promising a 21st Century Bill of Rights—akin to the “Second Bill of Rights” FDR spoke about in his 1944 State of the Union address, encompassing living wages, health care, education, affordable housing, a clean environment and a secure retirement.

“At the end of the day, the one percent may have enormous wealth and power, but they are just the one percent,” Sanders concluded.

“When the 99 percent stand together, we can transform society. These are my values, and that is why I call myself a democratic socialist. At its core is a deep and abiding faith in the American people to peacefully and democratically enact the transformative change that will create shared prosperity, social equality and true freedom for all.”