The way to win is with Santorum or Gingrich, and use the Bush 2000 or 2004 models.
Win the South and Midwest.
Then duke it out in Ohio, Nevada, New Mexico, Colorado and New Hampshire and possibly pick up Michigan or Pennsylvania (if Santorum is the nominee)
Rush Limbaugh spotted it in Michigan. Romney won the 7 districts around Detroit and Santorum ran a Reagan style campaign and won the other 7 districts including a couple places we expected Romney to win. (57 counties for Santorum, 26 for Romney)
Rush: Romney is winning like a liberal
http://www.freerepublic.com/focus/f-news/2853480/posts