"Change is coming," said the Massachusetts Democrat, who is considered a potential challenger to President Donald Trump two years from now. "This Nov. 6, Donald Trump's gonna hear all of us loud and clear."
Taking aim at Trump administration policies she said pit the wealthy against working-class Americans, Warren didn't mention any presidential aspirations in her keynote address to the Nevada Democratic Party's state convention in Reno.
But she said she's committed to building a party strong enough to compete in every race in the nation this fall, "and I'm willing to do my part to make that happen."
"I hope you're ready to fight uphill for as long as it takes, because I'm going up that hill, and I need you with me," she said
Warren said Nevada was one of the Democrats' few bright spots in 2016. In addition to being a rare battleground state that sided with Hillary Clinton, Nevada voters elected Democratic Sen. Catherine Cortez Masto as the Senate's first Latina and first woman to represent them there, she said.
She told a spirited crowd in a hotel-casino ballroom that their grassroots organization was the key in 2016 and predicted their energy will carry Democratic Rep. Jacky Rosen to victory in her bid to unseat Republican Sen. Dean Heller, the only incumbent GOP senator up for re-election in a state Trump failed to carry.
Warren was headed later Saturday to a Democratic fundraiser in Las Vegas.
Earlier in the day, Trump headlined the Nevada Republican Party's state convention in Las Vegas and raised money for Heller before holding a roundtable on tax reform.
Trump dubbed Rosen "Wacky Jacky" during his speech in Las Vegas. He noted that Rosen was in Reno with Warren and referred again to Warren as "Pocahontas" to ridicule her claims of Native American ancestry.
Trump said a vote for Rosen is "a vote for Nancy Pelosi," higher taxes and "weak, weak borders." He credited Heller with helping to pass the GOP tax cuts passed late last year.
Warren said Trump and the GOP leadership in Congress are beholden to corporate profits and polluters, and stand for "hatefulness, ugliness and cruelty." She said Trump has called immigrants "animals" and "ripped children from the arms of their mommas."
"I don't just want a party strong enough to drive Donald Trump and his enablers out of power," she said. "I want a party strong enough to take on the hard job of cleaning up the mess they'll leave behind once they are gone."
"Even when we stop the most corrupt Trump practices... this will still be a country where too many people are getting rolled by an economy - and a government - that's only working for the rich guys," she said.
Rosen targeted Heller's wavering positions on immigration, health care and Planned Parenthood in her Reno speech. She said he tells working-class Nevadans one thing, then votes lock step with Trump.
The president helped persuade Danny Tarkanian to drop his GOP primary challenge against Heller. Tarkanian then entered race for Rosen's House seat. Tarkanian is the son of legendary UNLV basketball coach Jerry Tarkanian.
Rosen, whose grandparents are immigrants, said Heller should use his clout to make sure children are not "ripped out of the arms of parents" and described the administration's "latest solution" to a disjointed immigration policy as "indefinite family detention."
"It's wrong, it's immoral," she said. "If Sen. Heller cares about doing what's right, he should have the backbone to personally talk to President Trump today about putting an end to this humanitarian crisis that has traumatized so many children."
Democrat Susie Lee, who is running against Tarkanian for Rosen's House seat, said Republicans have wrongly claimed to be the party of family values.
"When we talk about family values it means not having to make a choice between medical care for your family or putting food on the table," Lee said. "Family values means not taking children out of their parents arms and putting them in cages."
Other speakers included Cortez Masto and Clark County Commission Chairman Steve Sisolak, who pleaded for unity as he tries to become the first Democrat to capture the governor's mansion in Nevada in 20 years.
Sisolak, who faces Republican Attorney General Adam Laxalt in November, told the crowd that he knew that some had backed Democrat Chris Giunchigliani in the June primary. Term limits are forcing popular GOP Gov. Brian Sandoval out.
"No matter who you voted for, I think we all agree we can't allow Adam Laxalt to be governor," Sisolak said to cheers.
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