Eight states are holding primaries on Tuesday: Alabama, California, Iowa, Mississippi, Montana, New Jersey, New Mexico and South Dakota. It will be the busiest primary day of the year so far, as voters choose the candidates who will face off on Nov. 6.

Most of the attention this week has focused on California. Skip to the end if you want to read about that (or go straight to our live updates) — but first, here’s what you need to know about the other seven states in play.

New Jersey

Democrats think their path to retaking the House runs through the suburbs, and New Jersey is full of them. Five of its 12 seats are held by Republicans, and remarkably, Democrats have a shot at all five — even a couple districts that haven’t elected a Democrat since Jimmy Carter was president. You can read more about the campaigns here.

One of the most interesting primaries is in South Jersey, in the Second District, where Representative Frank LoBiondo is retiring. The effort to flip his seat has become a microcosm of a national battle: Jeff Van Drew, a conservative Democrat, says only someone like him can win the general election in a right-leaning district, while Tanzie Youngblood, his progressive challenger, is doubling down on the party’s liberal base.