As he prepares to run for a third term, Gov. Scott Walker of Wisconsin, ever the devotee of low-road, right-wing politicking, is hoping the Trump administration will allow his state to be the first in the nation to mandate the drug screening of childless individuals who apply for Medicaid help.

“It borders on immoral,” Lena Taylor, a Democratic state senator, warned, accusing Mr. Walker of indulging in a “meaningless contest to see how cruel and discriminatory we can be to the poor.”

Across the aisle, Senator Leah Vukmir defended Mr. Walker’s draconian initiative as it advanced last week in the Republican-controlled Legislature. “We know how to take care of our own,” she declared.

After failing on the national stage in the 2015-16 Republican primary jamboree, Mr. Walker has doubled down on his ideological roots back home. He is calling for drug testing of not only Medicaid applicants but also some food stamp applicants, so as to make welfare a “trampoline, not a hammock.” Fourteen other states have limited drug testing for some state welfare benefits. Mr. Walker, ignoring warnings that the courts are likely to find his goal unconstitutional, nevertheless wants to play the pioneer in forcing drug tests on people applying for Medicaid.