In Iowa, it's handshake-to-handshake combat

Everything that's wonderful about the Iowa caucuses is on parade in the frenzied days before the Jan. 3 showdown. It's handshake-to-handshake combat, retail politicking at its finest. You can find Michele Bachmann praying on a Sunday morning with the congregation of the Harvest Baptist Church in Fort Dodge and then by day's end admiring the beer-can Christmas tree at the Thirsty Dog Lounge in Manly. Or Newt Gingrich autographing a box of Corn Pops for a supporter at a rally at a Hy-Vee grocery in Mount Pleasant.

These intimate-yet-everyday settings constitute the power of the Iowa caucuses, which launched Jimmy Carter into political prominence in 1976 and have retained their political punch ever since.

Recent Iowa polls show Ron Paul slightly ahead of Mitt Romney, with Rick Perry and Gingrich in low teens, and the other candidates in single digits. (UPDATE: a new CNN-Time poll shows how volatile the field is. Romney is at 25 percent, Paul 22 percent, Rick Santorum 16 percent, Gingrich 14 percent, Rick Perry 11 percent and Bachmann 9 percent.)

In 2008, 73 percent of Republican caucus-goers were 45 or older.

"Normally they [older voters] have a lot of clout because they are the prime demographic that turns out to vote," Steffen Schmidt, a professor of political science at Iowa State University, told me. "They're highly motivated; their sense of civic responsibility is huge.  The same as everywhere, they're concerned about entitlement programs and benefit programs such as Social Security and Medicare."

Some facts about Social Security and Medicare in Iowa:

• One in five Iowans receive Social Security benefits.
• Three in 10 older Iowans rely on Social Security as their sole source of income.
• More than 519,000 Iowans - about 17 percent of the state's population - are on Medicare.

In an AARP-sponsored survey of likely GOP caucus-goers, 65 percent said they are opposed to cutting Social Security benefits and 67 percent said they are opposed to reducing Medicare benefits as  ways of cutting the deficit.

Evangelical Christians also speak loudly in the caucuses, first surfacing in 1988 to hand television evangelist Pat Robertson a surprising second place. Their clout may be diluted this year as three candidates - Bachmann, Perry and Rick Santorum - vie for their support. Though the main evangelical organization declined to endorse any candidate, a prominent evangelical pastor displayed his disdain for twice-divorced Gingrich by producing an ad calling him the "Kim Kardashian of the GOP."

So why does very white, very rural Iowa, with only 3 million residents, hold such sway over the presidential race?

"Iowa does not choose the president," Schmidt says. "It just gives candidates the opportunity to come early and sell their message."

Iowa was a winning formula for Barack Obama in 2008. It was not for Republican Mike Huckabee, who fizzled soon after his Iowa victory.