Possible Clues:

• A mountaintop of heather leads to natural spring coming from Wyoming, for example
• They're a blend of the main races
• A man overshadowed by another man? Old Bob in The Bostonians!
• Yanks
• Alaskans, Hawaiians, etc
• Mexicans have been in California for a long time
• Rains came (anag.)
• Some of them are 5 down
• Statesmen perhaps in car with same reforms
• Main races represented across the pond?