You’re not going to believe this, but tonight’s debate in Arizona will be the 26th for the remaining candidates for the Republican nomination. Rather than bore us to death, the debates have been been exciting and terrifying. And they have been the vehicle used by Mitt Romney, Rick Santorum, Newt Gingrich and Ron Paul to make a splash or catapult to front-runner status. Tonight will be no different.

Momentum is on Santorum’s side. Even though he’s caused quite a stir in the national press with past and present comments on theology, contraception, neonatal care and Satan, the controversy only seems to have helped him with primary voters. Santorum’s task tonight is to ensure the wave keeps rolling after tonight. And it could all depend on how he defends his positions on those issues. If you don’t think such answers matter, just ask Gov. Rick Perry about his “you don’t have a heart” retort on immigration from his very first debate. To his credit, Santorum has been rather good in the debates. Of course, he was a second-tier candidate. Tonight, the bull’s eye is on him.

Romney might be sitting around a table in the Southwest, but his mind will be focused on the upper Midwest. Michigan is his home state. He was born and raised there. His dad was its governor for three terms and also ran for president once. Only a tattoo of the mitt-shaped state somewhere on his body could make him even more pure Michigan. But as I explained in my last post, Romney is in a statistical tie with Santorum. If he can’t trip up the former Senator from Pennsylvania tonight, Romney and his super PAC have five days to reverse his momentum. Otherwise, Romney is kaput.

Then there’s Gingrich. The former House speaker is guaranteed to come loaded with a mouthful of fire. And when he breathes fire, everyone — opponents, debate moderators and the president — gets torched. Such red-hot rhetoric is what propelled him to the top of the GOP field — twice. Gingrich is hoping for a three-peat. While I don’t doubt Gingrich will do well tonight, he really has to knock it out of the park if he wants to hang on until Super Tuesday.

Oh, and Ron Paul. How could I forget the Texas congressman who forgot about the incendiary newsletters written under his name? Paul isn’t going anywhere no matter what. He’s Romney’s de facto blocker. As long as Paul is in the race siphoning off votes and aiming at anyone but Mitt, the inevitability of the former Massachusetts governor’s presidential ambitions remains alive.