They also rejected a proposal put forward by one of their own party members, Rep Sherae’a Moore, who sought to delay annual wage increases for one year for businesses with 20 workers or less.
With the bill passing in the House, it will now go to Democratic Gov John Carney, who is expected to sign the legislation.
Currently, Delaware’s minimum wage is $9.25 (£6.65) an hour.
Under the new legislation, the state would increase minimum wage by 13.5 per cent to $10.50 (£7.55), effective 1 January, 2022.
The minimum wage would then increase to $11.75 (£8.45) per hour in January 2023 and then to $13.25 (£9.50) per hour the following year, before reaching $15 in 2025.
Celebrating the bill’s success, Wilmington Democrat Rep Gerald Brady, the chief House sponsor of the bill, noted that “in the last 15 years, we’ve made 15 attempts to raise the minimum wage”.
Republicans, however, have warned that increasing wages could negatively impact small businesses and potentially lead to job losses, with GOP Rep Bryan Shupe asserting that the “dialogue” around the measure “has not been about empirical evidence, has not been about statistics, has not been about projections and analysis”.
“I really believe that instead of having a discussion on numbers and analysis, this was more of a political agenda,” Mr Shupe, who had proposed amendments that would have required studies of the economic impacts of the wage increases, told AP.
He also noted that the nonpartisan Congressional Budget Office (CBO) has previously concluded that a nationwide minimum wage of $15 an hour could see more people lose than jobs than be lifted out of poverty.
The CBO found that while raising the ceiling to $15 an hour by 2025 could lift 900,000 people out of poverty, it could also result in 1.4 million fewer jobs.
According to the Associated Press, legislative analysts have also estimated that the bill could cost taxpayers an additional $3.7 million (£2.6 million) in fiscal year 2024 to cover state employee wages, not including associated salary and wage compression issues.
Still, advocates for raising the minimum wage have celebrated the legislation’s success in Delaware as a major victory for workers, with US labor union activist Mary Kay Henry writing on Twitter: “This is the power working people have when we unite”.