One of those states is Florida, where the current minimum wage is $7.79 per hour. I asked Mike King, a grocery worker in Collier County earning the minimum wage, if the increase to $9 would make an appreciable difference in his life.

"There's no question about it," he said.

What may seem like small change to wealthier people, he said, would allow people in his situation to be at least a little better off: "I'd be able to buy better quality food some of the time. I could pay for gas and car insurance, so I could drive to my job instead of taking public transportation or riding a bicycle. And it would help me be able to pay my electricity and phone bills on time."

The federal minimum-wage law has always served a symbolic purpose beyond setting a specific number.

It has sent a signal to even the lowest-paid workers:

The country believes that what you do has value. The country will offer you a layer of protection that no one can undercut.

Today's column began with one question, so let's end it with another.

If there had never been a minimum-wage law passed -- if, as in the years before 1938, Americans today could be paid as little as employers could get away with -- and if, in 2013, someone in Congress proposed the first law ever that would guarantee workers a minimum wage. . . .

Do you think, in our current political atmosphere, such a law would have a chance of passing?

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