What to watch: New York will hold a series of congressional primaries on Tuesday with deep consequences for the general election battle for control of the House. Read more

Democrats hope to pick up multiple seats in New York, and they will pick nominees in what are expected to be some of the most contested districts in the country.

In the 19th District, seven Democrats are competing in a wide-open contest to run against Representative John Faso. In the 24th District, Democrats will decide who will be their standard-bearer against Representative John Katko, who is seen as a strong campaigner in a swing district.

There are also active Democratic primaries in the First District to take on Representative Lee Zeldin and in the 21st District to run against Representative Elise Stefanik in the North Country.

The Republican primary to watch is the 11th District on Staten Island, where Michael Grimm, a former congressman and felon, is trying to win back his old seat against Representative Dan Donovan. If Mr. Grimm prevails, expect Democrats to invest in Max Rose, a veteran who is their expected nominee.

In the New York City area, four House Democrats — Representatives Joseph Crowley, Yvette D. Clarke, Carolyn B. Maloney and Eliot L. Engel — all face more spirited primaries than they have in years but are nonetheless favored to win.

— MAGGIE ASTOR