Story highlights Hillary Clinton attended a union rally outside Donald Trump's Las Vegas hotel Monday evening

Clinton and other Democratic presidential contenders will participate in their first debate Tuesday

Las Vegas, Nevada (CNN) Hillary Clinton stopped at a union rally outside Donald Trump's hotel on the Strip here, taunting the Republican front-runner on the eve of the first Democratic presidential debate.

"Some people think Trump is entertaining, but it is not entertaining to insult immigrants and women," Clinton said.

Clinton joined about 500 members of the Culinary Workers Union -- a powerhouse in Nevada, with 55,000 members. The group is lobbying to organize the Trump International Hotel here.

"If you are going to run for president, then represent all of the people of the United States," she said. "I wanted to come by to lend my voice to all yours and I wish you well in these efforts."

She also stressed that workers should have the right to unionize and that, as president, she would protect those rights.

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