DES MOINES, IA -- The last GOP debate until IA: The seemingly endless debate parade of 2007 began -- on the Republican side -- at the Reagan Library in California, underneath Reagan's own Air Force One. It took us to Columbia, SC (where the GOP candidates sparred for the first time), to Manchester, NH (where audio/lightning troubles allowed Rudy to joke, after receiving a question on abortion and Catholic faith, that perhaps God was trying to punish him), and then to here in Des Moines (where Brownback -- remember him? -- targeted Romney on abortion). It continued on to the economic debate in Dearborn, MI (where Thompson made his first appearance), to Orlando, FL, then to St. Petersburg, FL for the YouTube debate, and then the Spanish-language one on Univision last Sunday. Now it's come to this: the final Republican debate before the Iowa caucuses; the Democrats have theirs here tomorrow. And with all of the cable news networks carrying this debate live, what would have been an under-watched afternoon affair in Iowa is perhaps turning into the most important debate of the cycle.1 p.m. today is the last 90-minute showdown.