Let loose from the political hothouses of Iowa and New Hampshire, the presidential candidates are roaming the real America — a hodgepodge of states with about as much in common as Arizona's saguaro cactus and Oklahoma's mistletoe.

From North Dakota to South Carolina, from Delaware's sandy shores to New Mexico's sandy desert, the seven states in Tuesday's Democratic contests are literally all over the map.

Depending on how much they agree on who's the best Democrat, they have the power to all but sew up the party's nomination, blow the race wide open or just leave pundits in a muddle.

As much as these primaries and caucuses will tell the nation something about its own mood, they will provide a crash course for the candidates about the diversity, the vastness and the variety of the country they hope to lead.

South Carolina tests the black vote; New Mexico measures Hispanic thinking; Missouri, at the middle of Middle America, is considered a rough gauge of the nation as a whole.

Arizona — among the fastest-growing and therefore most changeable states — is nonetheless forever associated with conservatives and the fiery rhetoric of Barry Goldwater.

In contrast, Delaware politics are so civil that winners and losers ride together in a post-election parade, and even bury a hatchet. After all, opponents are also neighbors in a state with about the same population as Indianapolis.

While Arizona and New Mexico struggle through drought, North Dakotans are bedeviled by floodwaters from rain-saturated Devils Lake. Oklahoma is tornado country; South Carolinians worry about hurricanes.

North Dakota's sparse population is shrinking. Despite its amber waves of grain, the flat prairie and stunningly cold winters seldom attract visitors — including presidential candidates.