With Republicans seen as less likely to hold their majority in the House, the party is focusing more on the battle for the Senate, where it is vastly outspending Democrats on ads.

© The New York Times

Four battleground congressional districts in the state reveal fault lines that are echoing nationwide.

© Rachel Wisniewski for The New York Times

Four battleground congressional districts in the state reveal fault lines that are echoing nationwide.

© Rachel Wisniewski for The New York Times