Mitt Romney is pulling away from the field, at least in the polls. Moreover, it is getting increasingly hard to argue that he is purely attracting moderate Republicans.

The Insider Advantage poll, which showed only a 2 point lead for him last week, now has him up by 11 points.

In national polling, he’s hit all-time highs in Gallup’s tracking poll (37 percent) and in the Fox News/Opinion Dynamics poll (40 percent). The Fox poll is instructive. On favorability, Romney has a 45 favorable, 38 unfavorable split. Newt Gingrich has an astounding 56 percent unfavorable rating, with only 27 percent favorable. Even Rick Santorum is in negative territory with 31 percent favorable and 34 percent unfavorable.

In the horse race, Romney has soared to 40 percent, up 17 points in a month, while his three principal challengers — Rep. Ron Paul (R-Tex.), Rick Santorum and Gingrich — are stuck in the teens. This belies the notion that he has a 25 percent “ceiling,” and it suggests that even if one or more of these candidates dropped out, Romney still might be leading. Interestingly Romney is rated a having the most positive campaign (27 percent), while Gingrich is labeled the “nastiest” (29 percent).

Plainly, Romney is riding high on the electability issue (63 percent say he’s the most likely to beat President Obama), but he is also now leading among Tea Partyers (31 to 20 percent over Santorum) and among self-identified conservatives (40 to 16 percent over Santorum). And it turns out that his venture capital background is a plus with 54 percent of the Republicans, a negative with 30 percent.

All of this suggests that it is not simply a divided conservative base that is allowing Romney to prevail. He is actually winning these voters over. This is not to say he can’t be slowed. But his opponents and pundits underestimate the degree to which he is solidifying his support among all factions within the party. This is the purpose, of course, of a primary: winnow the field, find a consensus candidate and unite to beat the other side. Right now Romney is the only candidate accomplishing that.