Early next month, Iowans will drive through the winter night to stand in groups at caucus locations to show support for their favorite presidential candidate. Bless them for their fortitude. Then in fast succession will come primaries in New Hampshire and South Carolina. Those three states are small enough for politicians to get to know individual voters at county fairs, coffee shops, and house parties.

But the intimacy of those early primaries can’t be sustained across a nation as big and diverse as the United States. That’s why all eyes are on Florida as the state’s Jan. 31 primary nears.