Trump, Waking a ‘Sleeping Giant,’ Helps Clinton Build an Unlikely Firewall

Stacey Abrams, Democratic leader in the Georgia House of Representatives, urging people to vote in Decatur, Ga., last week. The booming Atlanta suburbs, she said, had given Democrats a chance to win the state.CreditKevin D. Liles for The New York Times

CASA GRANDE, Ariz. — Since moving to Arizona 15 years ago, Nieves Lorenzo watched as Hispanics grew in numbers but only haltingly asserted themselves as a political force. Then came Donald J. Trump’s presidential candidacy.

“He has woken up the sleeping giant,” Ms. Lorenzo, a native of Venezuela, said as she stood in a local Democratic campaign headquarters here in the desert between Phoenix and Tucson.