It’s an almost archaic system in a small state waaaaay outside the Beltway that can make or break a candidate. You’ll be surprised by how few people decide who wins the first tally of 2008.

Take a peek at how the looming Iowa Caucus really works, courtesy of Politico’s Roger Simon:

The Iowa caucus is exquisitely difficult, the most daunting and complicated political process in America.

And because it is so difficult, it is a true test of the ground game: the ability of campaigns to identify, win over and deliver voters under conditions that are borderline bizarre.

“First-time caucus-goers get the shock of their lives,” says Michael Mauro, Iowa’s secretary of state. “They don’t know they have to stand in a corner, and there is no secret ballot.”

The process can take more than two hours. It is done only at night. People get to make speeches, argue and twist arms. And, afterward, neighbors sometimes stop speaking to each other for years.

Let’s say you are a Joe Biden voter and Biden turns out to be nonviable in your precinct.

The Edwards precinct captain, to use just one example, has to figure out how to get your vote.

He could tell you that Edwards will be ready from day one to be president of the United States.

Or he could promise to shovel your walk.

Simon knows whereof he speaks. He has covered every presidential campaign since Calvin Coolidge (well, not quite, but close). He’s an astute observer with a wry eye for detail. Check him out…