It’s time to acknowledge a milestone in the 2016 GOP primary. No, it’s not that Jeb Bush has broken his paleo diet. Rather, it’s that the leader in the Iowa polls is no longer the weakest frontrunner in caucus history!

Wisconsin Gov. Scott Walker is now polling ahead of where Mitt Romney was at this point in the 2012 cycle. Walker is up to 18.4 percent in an average of Iowa polls conducted in 2015; Romney was at 18 percent in surveys conducted through the first half of 2011. Looking at just the last five surveys, Walker is now up to 21.8 percent. That puts Walker in the company of past early Iowa leaders, such as Dick Gephardt in 2004 campaign and Rudy Giuliani in 2008.

Of course, neither Gephardt nor Giuliani won Iowa, and there’s still reason for caution. Throwing Walker’s polling average (18.4 percent) into a logit model with past early leaders indicates that Walker has only a 4 percent chance of winning the caucus. Realistically, his chances are almost certainly higher than that, yet none of the four Iowa caucus survey leaders polling at less than 30 percent at this point have gone on to win the caucus.

Unlike those eventual losers, however, Walker isn’t well known. In the latest live interview poll, conducted by Quinnipiac, 36 percent of Iowa caucusgoers could not form an opinion of Walker. Only 15 percent of Democrats couldn’t form an opinion of Gephardt in April 2003. Five percent of Republicans (paywall) had no opinion on Giuliani in May 2007. And 3 percent of Democrats (paywall) and 10 percent of Republicans (paywall) had no opinion on John Edwards and Romney, respectively. In other words, Edwards, Gephardt, Giuliani and Romney’s leads were more a function of high name recognition than Walker’s, which means Walker has a better chance than those candidates to expand his lead.

Needless to say, a Walker win in Iowa would be a big deal. While it likely wouldn’t eliminate Bush, it would make things very difficult for other conservative candidates to find a foothold going into the more moderate state of New Hampshire. Even though Iowa often doesn’t pick the nominee, no candidate has ever won a party’s nomination after coming in lower than tied for third place in the Iowa caucus.

We’ll have to see if Walker’s polling surge continues. He’s still not in great shape. But he’s clearly in better shape than he was a few months ago.