(CNN) The Rev. Al Sharpton​ may have very well introduced the next Democratic nominee​ when he welcomed a quintet of potential 2020 primary contenders to chilly New York City ​for a "temperature tour," as the host put it, on Friday, ahead of what's expected to be a hot and crowded nominating contest.

Mostly absent from the menu, though, as the five-star speakers chewed through their political visions on the third day of the National Action Network's 2018 convention, was talk of President Donald Trump. While Washington veers between agony and delight at the latest twist in his soap operatic presidency, the speakers in Midtown Manhattan kept clear of all things Stormy Daniels, James Comey and Michael Cohen.

New Jersey Sen. Cory Booker closed the bill of potential 2020 contenders, following his colleagues Sens. Elizabeth Warren, Kamala Harris, Bernie Sanders and Kirsten Gillibrand, with an explanation they all might have signed on for.

"I want you all to notice something," Booker told the lunchtime audience. "I'm just closing up on my remarks and I haven't mentioned Donald Trump at all. Why do I say that? Because it's not about him. It's about us and our problems and issues and challenges in this country did not start with Donald Trump."

The liberal and progressive energy that has risen up to meet Trump, Booker added, existed -- or should have -- before the 2016 election. Now, he said, "I am tired of people allowing someone who preaches hate to turn us into haters."

Harris went a step further. Refusing to mention Trump by name, she placed controversial White House policies and rhetoric ahead of his smothering personal style, then cast him in glaring opposition to past Oval Office occupants.

"Presidents of our country (in the 1960s) talked about, and I'm going to quote, 'the New Frontier.' They talked about, I quote, 'a Great Society,'" she said. "By contrast, in the last 15 months, we hear phrases like, I quote, 'American carnage' and a phrase that disparaged an entire continent of people with words I will not repeat here."

She turned, then, to the question Trump posed repeatedly on the campaign trail in 2016, when he asked black voters -- like so many in the audience at the NAN convention, "What do you have to lose?"

Reeling off a litany of controversial administration words and actions, like the recent suggestion by Trump that federal funding for historically black colleges and universities could be unconstitutional, Harris paused, meeting the groaning room as if sharing a personal aside: "This is what I get to see because I'm in DC," she said, "so I see it up close. I just came to share. These are notes from the field."

Gillibrand followed suit with what she presented as a studied warning to the Democratic Party more broadly, telling it "in the most absolute terms, that we should not court that hate for our own electoral survival, but we must shine a light on it for our moral survival."

The New York senator rounded out her program by offering, like Booker and Warren, some scripture and, all alone, positing the creation of "a universal jobs program."

Before turning over the stage to Gillibrand and Booker, Sharpton went a step further in making plain the purpose -- one of them, at least -- of the coming speeches.

"One of the reasons that we've had the presidential candidates come through is because we wanted to have them address the specifics that we deal with in our community," he said. "Now, none (from this year's group) have announced. They're on what we call a 'temperature tour' -- they're trying to test the temperature to see if they should announce."

Gauged if only by response in the rooms, all five will leave New York with ambitions at a boil. Sharpton provided each senator with thorough, warm introductions and all were, from the moment they began their strolls to the dais, welcomed by cheers and a swarm of amateur photographers. "President Harris in the house!" greeted the California senator and Sanders' arrival inspired one onlooker to turn and holler, "Feelin' the Bern!"

For Sanders, it was his second time in front of a predominantly black audience in less than 16 hours. On Thursday night, he joined with the Rev. William Barber II, co-founder of the new "Poor People's Campaign," at the Duke University Chapel in Durham, North Carolina, for a discussion on how to build a "moral economy."

Both at Duke and in New York, Sanders turned to the Martin Luther King Jr.'s April 1967 speech on the Vietnam War. One of the most controversial and politically radical of his public life, King at the Riverside Church on Manhattan's Upper West Side condemned American aggression in the region and tied it back to "the giant triplets of racism, extreme materialism, and militarism."

Sanders channeled that message on Friday, describing King as something more than a Civil Rights leader -- "a nonviolent revolutionary who wanted to see our nation undergo a revolution of values" against those "triple evils."

Meanwhile, the Vermont independent delivered a searing, if familiar, criticism of White House policy and the President's politics, but sough to avoid any protracted commentary on Trump, the tabloid character.

"Too much attention is given to sensational issues like Stormy Daniels, or who Trump fired yesterday, or the latest tweet that he sent out today," Sanders said , rapping the media for its priorities in coverage. "And they are not talking about the broad issues that impact tens of millions of Americans."

The sentiment seemed to run deep, along with a similar frustration, up in New York. During a talk about gun safety after Warren's speech, Minister Kirsten John Foy drew applause when he asked people to look away from the scene in Washington, where "a moron tweets every hour about some irrelevancy," and refocus on states, cities and smaller communities.

Still, Sharpton couldn't resist defending Warren from a familiar Trump insult as he warmed up the early arrivals ahead of her remarks.

"She's derided by the President because she stands up for all of us," he said. "You can judge your friends by who their enemies are. And he tries to deride her, calling her 'Pocahontas.' But to us, she's Sister Po Po."

With that, Warren took the mic and, unlike her colleagues, mostly focused on a single issue: home ownership. She began by discussing her own family's struggles to hold on to their house, then crossed over to a flowing historical analysis of racist housing policy and its legacy -- the decimation of black working class wealth.

"I'm not here to tell you that housing discrimination is any more important or any less important than any other issue facing black America today," Warren concluded. "I know I haven't personally experienced the struggles of African-American families, but I am here to say that no one can ignore what is happening in this country."