LAS VEGAS — They came, they cheered, they railed against President Donald Trump. And they pronounced "Nevada" correctly (Nev-AD-a, not Nev-AH-da), one of the truest signs the Democratic presidential field is recognizing the importance of the state's early caucuses in deciding who can win the nomination and represent an increasingly diverse Democratic Party.

It was the First in the West reception in the state's biggest city, and a crowded field of Democratic hopefuls had a single message for the 1,600 party activists who gathered to hear their pitches Sunday night. Since the event was not a debate but a series of individual appeals to a raucous crowd, the contenders saved their criticisms not for each other but for the man they all hope to oust from office.

That's if Congress fails, as Rep. Dina Titus, Democrat of Nevada, told the crowd, to "impeach the bastard right now," before the election.

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"This is a fight to end that national nightmare called Donald Trump," Sen. Kamala Harris of California told the crowd, which she had to ask to stop cheering so she could use her limited time to speak. "Justice is on the ballot in 2020 and that's why I'm running," she added.

Former Vice President Joe Biden hammered away at what he touts as his greatest asset – his experience – and President Donald Trump's efforts to derail his candidacy.

"There's going to be no time for on-the-job training," Biden said. "I can beat Trump. I can beat him. We choose unity over division. We choose truth over lies. We choose science over fiction. We will beat Donald Trump and we will beat him like a drum."

Trump is "a president who would rather lie than lead," Sen. Amy Klobuchar of Minnesota said.

Sen. Elizabeth Warren of Massachusetts criticized a Washington, D.C., government she said worked not for the people but for drug companies and other special interests. The situation now "is corruption pure and simple, and we need to call it out for what it is," Warren said.

The event marked the biggest single gathering of Democratic presidential candidates in Nevada since the campaign season began. The Silver State is home to the third nominating contest – its caucuses are Feb. 22 – but local officials say Nevada is the best test of which candidates have the staying power and organization to become the nominee.

"My personal feeling is, I don't think it matters what happens in New Hampshire or Iowa because those states are not representative of our country anymore," former Senate Majority Leader Harry Reid, a Nevada Democrat, told reporters before the candidate pitches. "You, the press, make a bigger deal out of Iowa and New Hampshire than you should."

Not only is Nevada far more diverse than either of the first two states in the primary process, but it presents challenges that test the mettle of contenders more acutely, Rebecca Lambe, a former Reid campaign manager who is now senior adviser with the Washington, D.C., political strategy firm Cassidy & Associates.

Nevada has more low-propensity voters, meaning candidates will need to develop good organizations on the ground to win here, she told reporters at a pre-event briefing.

The candidates are indeed stepping up their game here. Warren has opened nine offices in the state, including one in Elko – a rural area Democratic operatives here say candidates should not ignore, even though the vast majority of Nevadans live in two urban counties. Booker's campaign says he has visited eight times and is the first of the contenders to have visited rural Nevada. Biden, who is leading in polls here, held a town hall Saturday night in an historically minority neighborhood, where the former vice president received a warm reception from a diverse crowd.

Several candidates – including Biden, Warren and businessman Andrew Yang – held rallies or town halls while in Nevada for the First in the West reception, which also included appearances by Sen. Cory Booker of New Jersey and Sen. Michael Bennet of Colorado; South Bend, Indiana, Mayor Pete Buttigieg; former Housing and Urban Development Secretary Julián Castro; businessman Tom Steyer; former Reps. John Delaney of Maryland and Joe Sestak of Pennsylvania; and former Massachusetts Gov. Deval Patrick.

In a pre-speech group appearance, the competitors looked more like friends meeting for cocktails before seeing a show, laughing, chatting and pointing out curiosities in the packed ballroom. Warren supporters sported Mickey Mouse ear-like headbands with two enlarged pennies, a tribute to her wealth tax. Others stood together and held sparkly "NV4JOE" cutouts, while Sanders supporters waved multicolored, light-up wands.

Sanders walked across the stage to offer a hug to Warren, his rival for the progressive vote, while other fellow senators talked and clapped with the crowd.

And in his remarks, Sanders went back to the campaign theme he has endorsed since his 2016 run" a political revolution."

"Tinkering around the edges just won't do what has to be done," Sanders said, arguing for "Medicare for All" and the Green New Deal as his supporters stood and waved their rainbow rods.

Buttigieg, without mentioning Warren or Sanders, touted his "Medicare for All who want it" plan – a program he said offers government-sponsored care "while also trusting you to decide whether you want it."

Patrick, who just entered the race last week, hasn't qualified for Wednesday's debate or the December debate in Los Angeles. The First in the West appearance gave Patrick a chance, however, to reach a broad audience of early voters.

"It's not a fool's errand, or I wouldn't be in it," Patrick told reporters before he addressed the crowd.

And Democrats need to remember to focus on unity and mutual love of country, instead of using division as a strategy – even to get Trump out of office, Booker told the crowd.