A slew of top 2020 Democratic presidential hopefuls will be in Las Vegas Saturday to pitch their working-class credentials to the top Service Employees International Union (SEIU) as they seek to distinguish themselves from a crowded field of candidates.

Sens. Amy Klobuchar, D-Minn., Elizabeth Warren, D-Mass., and Kamala Harris, D-Calif., will be in attendance at the National Forum on Wages and Working People, along with former Rep. Beto O'Rourke, D-Texas, former Colorado Gov. John Hickenlooper and former Housing and Urban Development Secretary Julian Castro will be in attendance.

BIDEN TOPS SANDERS, O'ROURKE FOR LARGEST FUNDRAISING HAUL OUT OF THE GATE

The gathering has been arranged by both the SEIU and the Center for American Progress Action Fund.

The event gives candidates the chance to talk about kitchen table issues that could be key to a future Democratic nominee’s hopes of winning key swing states such as Pennsylvania, Michigan and Wisconsin -- where many working-class voters backed Trump in 2016.

The importance of that bloc of voters, in addition to the large field of candidates, means that unions could emerge as a significant influence on who gets the nomination.

“The clout of organized labor is going to be stronger than it has been in the recent past,” former Senate Majority Leader Harry Reid, a Nevada Democrat, told reporters on a conference call, according to Bloomberg News.

The SEIU has said that it is hoping for the nominee to commit to making it easier for workers to join a union and a federal $15 minimum wage. But so far the Democratic conversation has focused on liberal items such as Medicare-for-all, Green New Deal and more recently, whether criminals in prison should be given the right to vote.

IN LETTER TO AOC, BIG LABOR SAYS GREEN NEW DEAL COULD CAUSE 'IMMEDIATE HARM' TO UNION WORKERS

While some unions have expressed support for action on climate change, others have expressed skepticism about the Green New Deal in particular.

“We will not accept proposals that could cause immediate harm to millions of our members and their families. We will not stand by and allow threats to our members’ jobs and their families’ standard of living go unanswered,” the AFL-CIO Energy Committee wrote to Green New Deal sponsors Sen. Ed Markey, D-Mass., and U.S. Rep. Alexandria Ocasio-Cortez, D-N.Y. last month.

But candidates such as Klobuchar and Warren, in particular, have attempted to make their own blue-collar pitches. Klobuchar was in Vegas this month speaking to airline and rail workers at a union convention, while Warren joined Stop & Shop workers on a strike in New Hampshire. Sen. Bernie Sanders, I-Vt., campaign, meanwhile, has allowed its staff to unionize.

CLICK HERE FOR THE FOX NEWS APP

It is likely that former Vice President Joe Biden, who formally entered the race this week, will make blue-collar issues a cornerstone of his campaign -- but he will not be in Vegas on Saturday. Earlier this month he made an appearance at a rally for striking grocery store workers in Boston, and expressed his solidarity with union members.

“Wall Street CEOs and bankers did not build America, you built America,” Biden told a crowd of United Food and Commercial Workers International Union gathered outside a Stop & Shop market in the Dorchester neighborhood.

The Associated Press contributed to this report.