As Nation.com readers need no reminding, tomorrow residents of Iowa will become the first citizens in the country to weigh in on the presidential nominees. But not all residents of the state get to vote because it uses a caucus system (as does Nevada) instead of an open primary.

Watch this video by the youth voting group, Why Tuesday, if you’re confused about the caucusing.

Barack Obama, John Edwards, and Hillary Clinton have special sites and videos that offer instructions for how to caucus. Clinton emphasizes how easy it is, and Obama’s and Edwards’ step-by-step instructional videos make the point that caucusing is cool.

In comparison, New Hampshire, the second state to vote on a presidential nominee, holds its primary on January 8 and is the first to let its entire voting population vote on each nominee. New Hampshire treasures its placement in the primary calendar, and people there take its primary role very seriously. Candidates and campaign staff know that unless they’ve stood in a voter’s living room, the voters in these two first states don’t consider you a real candidate. There’s even a truism in Iowa that no one caucuses for a candidate that they haven’t met.

After New Hampshire, Michigan follows on January 15, and South Carolina — the first Southern state — holds its primary on January 26, with the controversial early Florida vote three days later. Then there’s Tsunami-Tuesday, as much of the rest of the country chimes in on February 5.

If I was an Iowa resident I’d caucus for Obama. Take The Nation‘s unscientific straw poll to tell us who you support and read The Nation‘s latest editorial to see what the magazine is thinking about the Democratic field.