Now that Super Tuesday has come and gone, the GOP presidential race has taken on a clearer shape. Here are the defining points as the contest heads into Kansas, Alabama and Mississippi:

The primaries are a two-man race between Mitt Romney and Rick Santorum. Newt Gingrich may have won his adopted home state of Georgia, but the former House speaker has had no traction beyond Georgia and South Carolina. Santorum, on the other hand, won Oklahoma, Tennessee and North Dakota and took the fight to Romney in Ohio.

For rock-solid conservatives, the winnowing is positive. Santorum is the more stable, compelling voice for culturally conservative, economically populist Republicans. Both Santorum and Gingrich cast themselves as warring against elites, but Santorum can do it with a smile and sense of mission. Gingrich appears too vindictive and calculating with his hard-right stands.

Santorum, however, must do more than come close in big states. The Pennsylvanian can’t keep suggesting he’d do better if Gingrich dropped out. He must win major battlegrounds to show his message would resonate in November.

Romney didn’t win Ohio as big as he would have liked, but he remains ahead in delegates and victories. The former governor crept ahead in Ohio because of his appeal in big urban, suburban areas. An appeal like that would help him in November, when the GOP nominee must win metropolitan voters.

Santorum, by contrast, did well in Ohio in smaller, rural communities. Small towns may be iconic America, but they are not where most Americans live.

Romney still struggles to connect with average Americans, but he’s tapping into a bigger vein of voters, especially those worried about the economy.

Barbara Bush was right when she said in Dallas this week that the GOP contest has grown too bruising. Internal competition of ideas can strengthen parties, but the former first lady was correct that the personal attacks have gotten out of hand. If the animosities don’t get buried soon, the eventual nominee will have to spend too much time winning Republicans in the fall instead of swing, independent voters. That would be devastating in a tight general election.

The split is about more than personality, too. It’s about the GOP’s business, mainstream wing vs. the party’s fervent populists.

The latter group has wrested control of the internal debate, pulling the former group further and further to the right. The business, mainstream wing that backs Romney needs to start pulling the party back toward the middle.

Otherwise, voters who want an entrepreneurial economic message but who also value women’s rights, strong public schools and a humane immigration policy will be driven away in November. It’s hard to see how that would help Republicans in any way.

Carl P. Leubsdorf is the former Washington bureau chief of the Dallas Morning News.