David Frum’s latest Newsweek column offers a free advertisement for former Arkansas Gov. Mike Huckabee’s new radio show — which is designed to challenge Rush Limbaugh’s dominance of the noon to 3 p.m. time slot.

Huckabee’s politics are emphatically conservative of course, both on social and economic issues. Yet his politics differ in important ways from those of the Limbaugh-influenced Republican electorate. “I don’t see a pathway for a person of my point of view getting through the land mine of the Republican primary. If that were to change in four years, if the Republicans were to get more serious about governing, not just campaigning—if we focused on what we were for and not just what we were against—then I might be a viable candidate.”

The less-strident Huckabee approach arises both from his experience as a long-serving governor in a Democratic-leaning state and from Huckabee’s famously genial temperament. “I have to believe that there are people who are highly opinionated but who actually find it informative and engaging to find out what the other side is thinking,” he says. “And not through a shouting match, but through an adult-level, civil conversation.”

The approach also reflects a business strategy as cleareyed as Limbaugh’s “play to the base.” Limbaugh’s audience not only skews old; it skews male. It was already 72 percent male in 2009—more male than that of almost any other program on radio or TV. Advertisers are not nearly as interested in talking to old men as to middle-aged women. If Huckabee can draw such women to his new program, as he has drawn them to his TV show, he will reshape the market.

Or not. If Huckabee appeals only to people who already shy away from the Limbaugh program, he’ll have a hard time making a dent in Rush’s ratings.