Apparently one good way to remain competitive in some GOP primaries is to urinate on the minimum wage, by casting it either as a case of Big Government run amok or as a key cause of our economic woes.

In a debate today in Missouri on KMOX, two of the three GOP candidate vying to take on Claire McCaskill for Senate seemed to come out for doing away with the minimum wage entirely. The third said it should not be raised at all.

The three candidates — GOP Rep Todd Akin, businessman Jon Brunner, and state treasurer Sarah Steelman — were all asked today by moderator Charlie Brennan whether they favored increasing the minimum wage.

Akin was the most forceful in suggesting it should be done away with. “I don’t think the government should be setting the prices or wages of different things,” he said. “I don’t think that’s the function of the government.”

Brunner came close. “We’ve got to let free enterprise reign in the marketplace,” he said, which in the context of the question, seems to suggest it should be done away with. He added that it was a burden on small businesses.

Only Steelman, in what may have been a slip-up, seemed to suggest clearly that it should stay put, though she said it shouldn’t be raised. “I’m not in favor of increasing it at this time,” she said. “I think it’s high enough as it is.”

It’s not hard to imagine that the minimum wage could become an issue in more Senate and House races, and even in the presidential contest. It’s already become a litmus test issue in the GOP presidential primary. After Mitt Romney said the minimum wage should rise along with the consumer price index or some other index, he took a hammering from the Wall Street Journal and the Club for Growth before quietly declaring that maybe the minimum wage shouldn’t increase, after all.

In the Missouri Senate race, which is going to be a tough one for McCaskill, the GOP candidates’ declarations on the minimum wage today could become a major issue. Dems will cast the statements as the latest example of Republicans being beholden to corporate benefactors, and skapegoating people on the lowest rungs of the income ladder for our continued economic suffering. Given that the issue will likely be key in other campaigns and even inthe presiential race, how this argument fares in a red-leaning state will be a key test case worth watching.