"Hart is a man of ideas, and ideas play well with the caucus voters."

For Republican primary and caucus voters, it is six percentage points.

So intense is the competition among the contenders that they hardly dare overlook any opportunity to influence caucus voters.

The lavish courtship of caucus voters brings a welcome boost to the economy of a state now rebounding from almost a decade of hard times in agriculture and manufacturing.

Republican candidates are making similar efforts, but their state party does not prepare a comprehensive list of previous caucus voters.

Filmmaker Kat Keene Hogue travels to Iowa to ask caucus voters one simple question: "What decided your vote?"

Iowa has no death penalty, and caucus voters there tend to oppose capital punishment, political experts say.

Recent polls of Republican caucus voters in Iowa, where Alexander claims to have the best organization, show him in fifth place with 7.7 percent, behind Dan Quayle.

While politicians normally try to avoid such divisive issues, in Iowa these topics deliver energetic caucus voters.

For Republican primary or caucus voters, it is plus or minus five percentage points.