Already a lightning rod for overhauling collective bargaining for state public employees, newly re-elected Republican Gov. Scott Walker wants to disrupt public assistance benefits in Wisconsin.

Walker, a conservative who's seen as a possible presidential contender in 2016, told CNBC on Wednesday he's working a plan for drug testing for people seeking unemployment checks and food stamps.

"If you want our help, we'll help you out temporarily. But we expect that you're going to find a job, and we're going to help you find that job," he said in "Squawk Box" interview. "Part of helping you do that means you're free from drugs so you can pass that [drug] test and be employed."

These kind of broad-based drug tests for state benefits would certainly face legal challenges. For example, a federal judge ruled that a similar law in Florida championed by Republican Gov. Rick Scott violated the constitutional guarantee against unreasonable government searches.

"It just seems ridiculous to me that if we're going to give people public assistance ... why we would set them up for failure," Walker said.

He refused to say whether he wanted to run for president, but he did tout his conservative credentials, saying he's a "common-sense conservative who gets things done" and it's time for a bold Washington outsider.

"I think someone like that … a chief executive at the state level who can take on the mess in Washington is the best pick for Republicans two years from now," Walker said. He added that fellow Wisconsin Republican Paul Ryan, chairman of the House Budget Committee, would make a good choice for president because he thinks like a governor.

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