A push to slash the standard workweek from 40 hours to 32 achieved a breakthrough this week, gaining a foothold in the Senate with a proposal that would require businesses to offer the 32-hour workweek but preserve employee pay.

The bill, put forward by Sen. Bernie Sanders, I-Vt., drew praise from labor advocates who tout the benefits of the reduced hours not only for workers' wellbeing but for the productivity benefits enjoyed by their employers.

However, political analysts who spoke to ABC News cast doubt on the measure's chances of passage in a divided Congress where opposition from Republicans is all but certain and even the extent of support among Democrats remains unclear.

"It's so hard to get anything passed, especially when you have such high levels of polarization. It doesn't take a lot to stop legislation," Richard Hall, a professor of political science at the University of Michigan, told ABC News.

"You'd have to imagine a very different political world than what we have now," Hall added.

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Proponents of the measure point to the output gains generated by workplace technology, including recent improvements in automation and artificial intelligence.

The standard 40-hour workweek became a federal requirement in 1940, when rudimentary machinery made for diminished worker productivity. Today, much more output can be achieved in fewer hours, advocates say.

A study out of the United Kingdom last month found nearly 9 in 10 companies opted to retain a four-day workweek after participating in a temporary pilot program.

Support for the measure in Congress, however, remains scant. The proposal made by Sanders on Wednesday carries the support of just two other lawmakers, California Democrats Sen. Laphonza Butler and Rep. Mark Takano.

"I don't see this current iteration of the law getting through Congress," Lynne Vincent, a professor of industrial and labor relations at Syracuse University, told ABC News.

A near-identical bill proposed by Takano in the House last year gained the support of just seven colleagues in that chamber.

Some Republican lawmakers voiced opposition to the newly announced measure in a hearing of the Senate Committee on Health, Education, Labor and Pensions on Thursday.

The proposal amounts to an effective pay increase forced upon businesses, Sen. Bill Cassidy, R-La., said, predicting that the 32-hour workweek would "destroy some employers."

"They would ship those jobs overseas or they would automate to replace those workers for whom they have an increased expense, or they would dramatically increase prices to stay afloat," Cassidy added.