NEW YORK (Reuters) - Democratic U.S. Senator Kirsten Gillibrand delivered a fiery repudiation of U.S. President Donald Trump on Sunday at the doorstep of one of his most famous properties, making it clear she will not pull her punches in seeking to replace him.

“President Trump is tearing apart the moral fabric of this country,” Gillibrand declared to hundreds of supporters, with Trump International Hotel and Tower - which she called a “shrine to greed, division and vanity” - as a backdrop in midtown Manhattan. “Our president is a coward.”

The speech, the first since Gillibrand formally launched her 2020 campaign last week, and its location were intended to show voters that she will attack Trump directly, in contrast to some Democratic rivals who have hesitated to focus on the Republican president early in the 2020 campaign.

While some candidates, most notably Vermont Senator Bernie Sanders, have harshly criticized Trump, others have largely avoided using his name, as Democrats try out different tactics for confronting the divisive president.

Gillibrand’s aggressiveness could endear her to angry Democratic voters who are desperate to defeat Trump next year.

“She’s trying to differentiate herself,” said Maria Cardona, a former senior adviser to Hillary Clinton. “It’s a pretty crowded field. She’s not really in the middle of it, and she needs to be in the middle of it.”

Though Gillibrand’s formal campaign for the Democratic nomination began last week, she announced she was exploring a candidacy in January and spent the last two months visiting states such as Iowa, New Hampshire and South Carolina that will hold early nominating contests next year.

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But she has struggled to build momentum among a group of more than 15 announced and potential candidates, including five other sitting senators and former Vice President Joe Biden, who is expected to join the race soon.

“Gillibrand simply lacks the star power or national prominence that would lead to extensive free media time,” said Patrick Murray, director of the Polling Institute at Monmouth University.

In recent surveys, Gillibrand has remained stubbornly mired in the 1-percent range, while other first-time presidential candidates like Kamala Harris and Elizabeth Warren, both U.S. senators, have shown more competitiveness.

The race remains in its infancy, however, with the first nominating contest in Iowa still 10 months away.

“Most voters are just learning the candidates’ names,” said Jesse Ferguson, a senior spokesman for Clinton’s 2016 presidential campaign. “Right now, the priority for a candidate is to introduce themselves and show what their values are and how that’s the answer to what we have in the White House.”

Gillibrand, known as a moderate when she served as a congresswoman from upstate New York, has refashioned herself into a staunch progressive.

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In her speech on Sunday, she expressed support for several liberal policy goals, including universal paid family leave, the environmental agenda known as the Green New Deal, Medicare-for-all and legalizing marijuana.

She also referenced her own efforts in the Senate to address sexual assault in the military and on college campuses and to secure equal pay for women.

But it was her pointed criticism of Trump that may help separate her from the pack.

“I’m proud to have stood up to Donald Trump more than anyone else in the U.S. Senate,” she said, referring to her voting record.

Several supporters said they appreciated her willingness to go after Trump, even if it risks an insulting counterattack from the famously no-holds-barred president.

“We need to fight Trump head on,” said Kathleen Nichols, 62. “Kirsten’s a fighter.”

Eric Seyfried, 53, said he had donated money to Gillibrand for years, starting with her first congressional run in 2006.

“If you’re afraid to take on a bully because the bully is going to come after you, maybe you’re not supposed to be president of the United States,” he said.