SAN JUAN, Puerto Rico (CNN) Sen. Elizabeth Warren said Tuesday that President Donald Trump treated Puerto Rico with "extraordinary disrespect" in his response to the devastation that followed Hurricane Maria, singling out for scorn the Trump administration's recent draft proposal to divert the island's storm relief funding to pay for his border wall.

In an interview on the campus of Puerto Rico's oldest public university, Warren, making her first trip here since entering the Democratic presidential primary on New Year's Eve, tied the President's insistence on using federal money for the proposed barrier to his false claim that nearly 3,000 Americans in Puerto Rico 'did not die' in the aftermath of Maria as researchers had reported.

"Donald Trump won't even pay the people of Puerto Rico the courtesy of acknowledging the deaths of the people they love," Warren told CNN. "Now that he's caught in this fight to try to find funding to be able to build a monument to hate on the southern border of the United States, he looks over to Puerto Rico to see if he can take away unspent dollars that were designated for relief efforts."

Warren is the second Democrat with presidential aspirations to visit the island, a US territory that will hold a presidential primary next year, in 10 days. Julián Castro, who was secretary of housing and urban development during the Obama administration, made Puerto Rico his first campaign stop. Warren's visit -- and the prospect of other hopefuls to follow -- underscores the island's growing importance to Democratic voters around the country, many of whom remain angry and frustrated over the Trump administration's post-hurricane response.

"(Trump) announced that only a handful of people had died as a result of the hurricanes and, of course, congratulated himself on that," Warren said, recalling Trump's initial boasts over a death toll that, at the time, was believed to be in the teens

With Gov. Ricardo Rosselló at his elbow, Trump said at a news conference here in October 2017, "Every death is a horror, but if you look at a real catastrophe like Katrina and you look at the tremendous -- hundreds and hundreds of people that died -- and you look at what happened here with, really, a storm that was just totally overpowering ... no one has ever seen anything like this."

In remarks later in the day at the Alejandro Tapia y Rivera Theater in San Juan, Warren called for the Federal Emergency Management Agency top official to step down.

"If accountability means anything, Brock Long should take responsibility for his failures. He should resign as head of FEMA," she said. "And if he isn't willing to do that, he should be fired."

Warren on Tuesday also discussed her worries that the billions of dollars allocated by Congress for disaster relief would "work their way through the system and end up in the hands of the operators of vulture funds on Wall Street" -- an argument she returned to hours later -- effectively wiping out the island's already decimated poor and working class.

"Money that comes to Puerto Rico should be used only here in Puerto Rico," Warren told CNN. "It should be used to rebuild Puerto Rico. It should not be used to pay a bunch of Wall Street speculators while they try to cut services for the people of Puerto Rico."

After the storm, which collided with an island in the depths of a debt crisis that critics say was worsened by predatory lending, there has been an exodus of especially young Puerto Ricans, including a generation of students whose pursuit of higher education has been stalled by austerity budgets -- which Warren described in her speech later as "twin catastrophes."

"First, change the law to create a path to real, comprehensive debt relief for disaster-stricken places like Puerto Rico," Warren said, touting her "Territorial Relief Act, which would give this island a chance to get out from under the thumb of Wall Street speculators."

Angélica Jiménez, a 22-year-old graduate student at the University of Puerto Rico, called Warren's visit and the expected coming influx of candidates "bittersweet" and lamented past candidates' tendencies to drop in ahead of the primaries and then essentially forget the island. The upside, she said, is the size of the group that quickly formed around Warren at a park bench on the San Juan campus.

"There is a bigger interest in the island as a whole and in its education system and in its financial structure," Jiménez said, "and how it's being put in a choke hold by investors and companies and (other powerful institutions)."

Warren's early visit to Puerto Rico, only three weeks after she announced she'd explore a run, further highlights how crucial the minority vote -- including from the Puerto Rican diaspora, which will have a stronger say in the 2020 elections now that so many are living in states with electoral votes (the island does not vote in presidential general elections) -- is for Democrats with presidential ambitions.

Starting with her announcement on New Year's Eve, Warren has zeroed in on economic disparities along racial lines, lamenting the disproportionate pain felt by black and Hispanic Americans. Asked how she can win over African-American voters in a state like South Carolina, where she will travel on Wednesday, Warren doubled down.

"Race matters," she said. "It is part of what's gone wrong in our economy and something we need to address head on, and that's exactly what I plan to do."

Warren also addressed the entry of Democratic Sen. Kamala Harris into the primary mix, describing the diverse and growing 2020 field as an "exciting moment" for the party.

"It is a reminder that Democrats have a lot of ideas and a lot of energy," she told CNN. "And we're ready to get out there and talk about the big difference between us and Donald Trump and the Republican administration."

But the shape of the race for a chance at replacing him remains difficult to discern. Where the candidates overlap and diverge, especially amid the party's broad shift left, will likely remain somewhat of a mystery until they begin their slate of debates in June. Asked about the $3 trillion tax plan that Harris could make a cornerstone of her bid, Warren said she had not yet seen the proposal.

Warren was clear on one point: The emergence of several female candidates -- four over the first three weeks of the year -- in the race for the White House was long overdue.

"Isn't is exciting?" she said. "This is the first time this has happened in American history, and in my view it should have happened a long time ago. I think it's terrific."