Sen. Bernie Sanders introduced The Workplace Democracy Act, a bill that would strengthen labor unions.

Sanders said the plan would help boost wages and reduce income inequality.

The plan is unlikely to gain traction in the current Congress, but signals a priority for Democrats going forward.

Sen. Bernie Sanders on Wednesday introduced a plan that he says will boost wages by strengthening labor unions.

Sanders' Workplace Democracy Act would make it easier for workers to join unions and strengthen unions' negotiating power.

The plan is cosponsored by an array of Democratic lawmakers, including possible 2020 presidential hopefuls Sens. Elizabeth Warren, Kamala Harris, and Kirsten Gillibrand.

Sanders, an independent and a 2016 Democratic presidential candidate, said the plan was designed to help workers in the middle class.

"In order to strengthen America's middle class, we must make it a priority to restore workers' rights to bargain for better wages, benefits, and working conditions," Sanders said in a statement. "That is the goal of the Workplace Democracy Act."

Here's a brief outline of the plan's provisions. It would:

Allow the National Labor Relations Board, or NLRB, to certify a union if a majority of workers sign up. Such a move would allow unions to form easier than under the current election process. Labor advocates say elections allow for more interference from businesses trying to union formations. Such a move would allow unions to form easier than under the current election process. Labor advocates say elections allow for more interference from businesses trying to union formations.

Compel businesses to begin negotiations with a prospective union within 10 days . That would prevent companies from ignoring union requests and speed up the recognition process. The bill would also give businesses 90 days to reach an agreement through negotiation before compelling the two sides to go to arbitration.

Expand the definition of employer. Currently, many companies in the so-called gig economy (like ridesharing companies) consider workers as independent contractors. By expanding the definition of employer, workers could form unions and collectively bargain with these types of businesses.

Allow secondary boycotts. That would allow unions to boycott suppliers and companies associated with a business that was in a labor dispute.

Compel companies to disclose anti-union activity. This would force businesses to publicly disclose funding to anti-union consultants and distribution of anti-union materials to workers.

Sanders said the reforms would give workers more power and help boost lackluster wage growth in the US.

"Declining unionization has fueled rising inequality," Sanders said. "Today, corporate profits are at an all-time high, while wages as a percentage of the economy are near an all-time low. The middle class is disappearing, and the gap between the very rich and everyone else is growing wider and wider."

April's jobs report showed that average hourly earnings grew only 2.6% year-over-year and remained below pre-recession levels despite the fact that the current economic expansion just became the second-longest in US history.

Union membership has been gradually falling for decades, and some academic studies have connected the decline to rising income inequality and slower wage growth. Workers in unions consistently earn higher wages than their non-union peers, studies have shown.

Sanders first introduced legislation called the Workplace Democracy Act as a member of the House in 1992, but it stalled. The Vermont lawmaker reintroduced similar House legislation in 1994, 195, 1997, and 1999. He also introduced a Senate version in 2015.

Given Republican control of the White House and Congress, the bill is unlikely to pass anytime soon. But, it does signal that unions and labor could be a key focus for Democrats in the next presidential election.