U.S. Democratic Presidential Contender Pete Buttigieg on Saturday cautioned Democrats about nominating Bernie Sanders, after the Vermont senator solidified his front-runner status with a decisive victory in the Democratic presidential caucuses in Nevada.

Joe Biden was on track for a second-place finish that would give his struggling campaign new hope.

Buttigieg told supporters, "I congratulate Senator Sanders on a strong showing today, knowing that we celebrate many of the same ideals. But before we rush to nominate Senator Sanders in our one shot to take on this president, let us take a sober look at what is at stake for our party ... we absolutely must defeat Donald Trump and everything that he represents in November."

Buttigieg added, "And that is a real difference from Senator Sanders revolution with the tenor of combat and division and polarization leading to a future where whoever wins the day, nothing changes the toxic tone of our politics."

He continued, "I believe the only way to truly deliver any of the progressive changes that we care about is to be a nominee who actually gives a damn about the effect you are having from the top of the ticket on those critical front-line House and Senate Democrats that we need to win."

Watch Pete Buttigieg’s Full Speech After Nevada Caucus Loss | NBC Nightly News

Sanders had 44% of the county convention delegates in Nevada with about 11% of the precincts reported, as results were slow to roll in six hours after the caucuses began. Biden was a distant second to Sanders with 25%, but ahead of Buttigieg of South Bend, Indiana, in third with 15%.

"We still have a little bit of time before everything closes today. But as long as he's finishing in the top three, we're happy. And we're in it. We're loyal to the end," said Buttigieg supporter Shonna Mackelprang, a 50-year-old veteran.

"So far, I feel pretty good. I'm excited. We had a good day," added Caitlin Escobar, a 33-year-old teacher who has been campaigning for Buttigieg for months.

Sanders rode a wave of backing from a diverse coalition of young and middle-aged voters, Latinos, union members and white college-educated women to a win in Nevada, showing signs of expanding support for his front-running campaign beyond his long-standing core.

Senator Elizabeth Warren was trailing in a disappointing fourth with 8% in Nevada, where voters poured into more than 250 sites around the state. Senator Amy Klobuchar and activist billionaire Tom Steyer were well back at 4%.