Missouri is “a relentlessly average state”--according to University of Missouri professor David Robertson--with an economy that mimics the national economy, and demographics similar to the nation as a whole. “Missouri is a natural laboratory” of American politics, Robertson says--if it’s happening there, there’s a good bet it’s happening countrywide. The primaries also echo national trends: Obama and Clinton are tied, pitting the Democratic establishment against the party's “mavericks” and Obama’s strong local organization (which benefits from volunteers out of nearby Illinois). McCain has a solid lead over Romney and Huckabee, who are splitting the conservative vote.

Delegates: Democrats, 88; Republicans, 58.

Format: Proportional, open primary for Democrats. Winner-take-all, open primary for Republicans.

Recent Polls: The most recent polls were taken February 1-3, showing Obama leading Clinton 47-42 with 12 percent undecided, and McCain leading Huckabee and Romney 35-27-24.

Democratic In-State Fundraising: Barack Obama $790,822; Hillary Clinton $738,507.

Republican In-State Fundraising: Mitt Romney $842,240; John McCain $239,690; Ron Paul $173,616; Mike Huckabee $124,269.

Endorsements: Clinton has the support of the Democratic establishment, including figures like Dick Gephardt, whose influential aide Joyce Aboussie is a solid Clinton backer. Obama is riding on support from political figures “who have succeeded despite the party;” insurgent politicians like Senator Claire McCaskill--who ousted incumbent Democratic Governor Bob Holden in a 2004 primary--are taping ads for Obama, lending him much-needed legitimacy. The St. Louis papers, including the St. Louis Post-Dispatch and the St. Louis American (an important African-American weekly) endorsed Obama, underscoring the recent national shift of blacks to Obama. The Kansas City establishment, including the Kansas City Star and Kansas City Rep. Emanuel Cleaver II, is backing Clinton.

Demographics: St. Louis, in the east, is a heavily unionized industrial city with a large African-American population now sympathetic to Obama. Kansas City, in the west, is America’s “easternmost Western town,” with attendant cattle-oriented history. The north mimics rural Iowa, while the rapidly-growing exurbs in the southwest and center of the state are an important source of votes for both parties. According to University of Missouri professor Terry Jones, the state’s Democratic electorate is based in the St. Louis area (split between African-American voters to the north, and suburban whites--who largely support Clinton--to the south, west, and in nearby St. Charles county); in the Kansas City area, where the establishment backs Clinton; and in Boone county, where large numbers of university students may turn out for Obama. One trend to watch is the movement of Democratic men in the suburbs and rural areas towards Obama. Missouri has an open primary, so the Democratic race could be influenced if McCain peels off independent votes from Obama.

The conservative southwest is a rapidly growing Republican stronghold with many evangelical families, as are exurban communities like St. Charles County, across the river from St. Louis--areas that should be a bonanza for Huckabee even as Romney struggles to gain the conservative vote.

Get a rundown of other states at play at TNR's Super Tuesday Primer, updated with new states every day leading up to February 5.