"Russ better watch out."

That remark was heard more than once from Democratic activists and others after Republican business executive Tim Michels' surprisingly strong victory in the U.S. Senate primary Sept. 14.

Michels buried his better-known opponents, state Sen. Bob Welch, R-Redgranite, and car dealer Russ Darrow, immediately drawing the attention of senior national Republican strategists. If Bush can win Wisconsin, they figure, Michels can come in on the president's coattails, knocking off Feingold and building the Republicans' slim margin in the U.S. Senate.

For Feingold, Michels is a more serious challenge than either Darrow or Welch would have offered -- Darrow because of his inexperience and unfocused politics, Welch because of his far-right ideology. Feingold would have handily beaten either.

But Michels is a different breed of cat: He's every bit as conservative as is mainstream Republican philosophy these days on abortion, gay marriage, taxes and other issues, but there are pieces of his resume and his views that edge away from the Bush administration, or the far right, to something mildly centrist.

He has, for instance, come down hard rhetorically on corporate cheaters, and supports the importation of Canadian prescription medicine.

Michels is also able to attach himself personally to the homeland security issue through his 12 years service in the Army. Since 9/11, candidates with military experience are successfully highlighting their service in campaigns (the exceptions being George W. Bush, whose Air National Guard service record is, at best, spotty, while war hero John Kerry had his Vietnam service trashed by Bush's Swift Boat surrogates). So, much of Michels' publicity emphasizes his military career.

A footnote to this: Feingold catches a bit of a break because Michels cannot claim combat experience. But Michels' military ID has become standard terminology even in newspaper headlines and one-line biographical news summaries. That means the Oconomowoc construction executive has won one small battle to control the development and definition of his political persona.

Bottom line: Michels is not Mark Neumann, the Republican congressman Feingold defeated in 1998. Neumann made it close, but his deer-in-the-headlights appearance and sometimes over-caffeinated manner made Feingold look calm and collected; more senatorial, if you will.

And in 1998, the country was not at war. Military service was not as valuable on a politician's resume as it can be now. At 42, nine years Feingold's junior -- but not so youthful as to look juvenile -- Michels' candidacy is nicely timed.

This is not to say that Feingold is doomed. Far from it. He has worked the state hard for 12 years, regularly holding town meetings, managing offices in Washington, D.C. and in the state that do excellent constituent work. The political identity that he has carved out -- maverick senator, heir to the Proxmire legacy, Wisconsin Progressive -- all resonate deeply throughout the state.

And he is the incumbent. And a long-time elected official, who knows how to run scared without running panicked.

Michels will benefit from a big infusion of Republican financing that will help saturate the airwaves with top-shelf political ads. Feingold has been spending heavily, too, though some of his ads try too self-consciously to replicate the charming cuteness of his earlier campaigns, when he was less well-known and not facing a party led by take-no-prisoners Karl Rove.

Again, this is 2004, not 1998, and that's why Republicans are eyeing Feingold's seat after Darrow and Welch flamed out. And it's why Democrats are worried.

If Feingold runs a perfect campaign, his experience across the state should win him a third term. But he better watch out.

James Rowen is a Milwaukee writer and consultant who used to work for John Norquist.

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