The one thing I’ll be watching for in the first Republican presidential debate

There are going to be a lot of entertaining characters on the debate stage tonight, but the only one I’m really interested in watching is the least colorful of the bunch: Wisconsin Gov. Scott Walker.

Walker is, in a word, boring.

But he’s also the guy with far and away the most plausible shot at toppling Jeb Bush and becoming the Republican Party’s nominee in 2016. To do it, he’s going to have to do something he hasn’t done so far in the campaign — say mean things about Jeb Bush and likely about Jeb’s whole family. You don’t take down the frontrunner without attacking the frontrunner, and a debate is the ideal time to attack the frontrunner because a debate is a time when people are supposed to debate.

And yet I’m not entirely sure he will do it. After all, on paper Tim Pawlenty looked like a strong challenger to Mitt Romney. He was more consistently conservative than Romney. And he’d run and won in a liberal-leaning Midwestern state.

But he was too Minnesota nice to kick ass.

As best I can tell, Scott Walker is a genuinely boring person. His habit of tweeting about his haircuts seems to be completely sincere. He celebrates his anniversary with a celebration themed around Ronald Reagan’s birthday.

In many contexts, Walker’s banality plays to his advantage, as Brian Beutler has written. Both the media and swayable voters tend to pay more attention to affect than to public policy. And while Ted Cruz seems like a maniacal right-winger, Walker seems like a mild-mannered accountant. That’s a great way to sell aggressive tax cuts and drastic attacks on labor union political power in a politically moderate state.

But it is not a good way to win a primary.

To win a primary he’s got to bring it, in primetime, on the big stage, and show that he’s not some two-bit Midwestern nobody who’s obviously outclassed by the guy with the pedigree and the Rolodex and the $100 million Super PAC bankroll. If he throws some sharp punches, he could win this thing. But he’s going to have to take a risk and do it.

The risk for both Walker and the viewing public is that this debate is actually going to be a snoozefest. The candidates on the stage have released very little in the way of policy plans, and they frankly don’t have much in the way of big-picture ideological disagreement. It’s easy to imagine a world in which they all get up there and ritually denounce Barack Obama, Iran, Hillary Clinton, ISIS, and illegal immigration as the direst threats to the American Way of Life in history.

If a snoozefest starts to emerge, Walker is really the only guy with an incentive to break up the party and get real.

Which is to say that it’s easy to agree that Obama has been a disaster and Hillary will be a disaster. What’s hard is to admit that Republicans have been part of the problem, too. Republicans like Jeb’s brother, who pushed bank bailouts and amnesty for illegal immigrants and a federal takeover of the curriculum. And, hey, Jeb has famously endorsed the last two of those things and the way he’s been soaking up Wall Street bucks lately means he probably likes the bailouts too.

In other words, it’s hard to debate, but a debate is what the Republican primary debate is supposed to be about. Walker, more than any other candidate, is the one with the means and the opportunity to open up a real debate about questions of substance — especially the Bush-era GOP’s handling of the financial crisis. But to do it he’s going to have to get out of his aw-shucks comfort zone and throw down.