The potential benefits from the $1 trillion infrastructure package that's now passed the U.S. Senate are not fully reflected in the stocks of industrial firms like steelmaker Nucor , CNBC's Jim Cramer said Wednesday. Speaking from the New York Stock Exchange on "Squawk on the Street," Cramer acknowledged the recent big moves in Nucor and some of its rivals, such as U.S. Steel and Cleveland-Cliffs . As of Tuesday's close, shares of Nucor were up 21.54% in the past month and 156.18% over the past year. U.S. Steel is up 15.36% in the past month and up nearly 259% in the past 12 months. Cleveland-Cliffs, which mines iron ore and makes steel, is up 15.34% in the past month and 331.51% in the past 12 months. Investors have flocked to the companies as part of a broader rotation into cyclical stocks that benefit from the U.S. economy's expansion from its Covid-induced recession. The infrastructure bill — which still needs approval from the House of Representatives before President Joe Biden can sign it into law — adds another layer to the investment case for the likes of Nucor, U.S. Steel and Cleveland-Cliffs. "Right now this industry is doing incredibly well. But a lot of people feel it's going to plummet next year. I think this infrastructure bill means it won't," Cramer said. "I think it makes a lot of sense to still buy the stock," Cramer added, referring specifically to Nucor. Asked by "Squawk on the Street" co-host David Faber whether those stocks already reflected the increased demand that would be injected by massive government spending on roads, bridges and various other construction projects, Cramer said he did not believe that was the case. "No, I do not because Nucor sells at 6 times earnings and Cleveland-Cliffs sells at 5 times earnings," the "Mad Money" host said. Those figures are for 2021 earnings. Cramer said the infrastructure package will undoubtedly benefit these companies if Biden eventually signs it, citing as evidence comments made by Nucor's chief executive, Leon Topalian, in an interview Tuesday on "Mad Money." "Seeing bipartisan support in approval through the Senate is such a huge step," Topalian told Cramer, adding that the steelmaker is ready to help "rebuild this country." Disclosure: Cramer's charitable trust owns shares of Nucor.