(CNN) — Eight states are holding primary elections today, making it the biggest primary night of 2018 so far.
All eyes are on California, where polls close at 11 p.m. EDT. The Golden State has a “direct primary,” commonly known as a “jungle primary,” which means the top two candidates will advance to the general election in November regardless of party.
That has Democrats in California concerned that their candidates might get locked out of races that are key to their chances of retaking the US House majority in November. Of particular concern are the House races in three districts: the 39th, the 48th and the 49th.
In total, there are 10 House races Democrats believe could be competitive in November.
There are also two pivotal statewide elections taking place in California. Democratic Sen. Dianne Feinstein is widely expected to advance to the general election, but her opponent will be decided from the results coming in tonight. In the race for governor, former San Francisco Mayor and current Democratic Lt. Gov. Gavin Newsom narrowly leads a field whose other top contenders include Democrat Antonio Villaraigosa — a former Los Angeles mayor — and Republican businessman John Cox. In both races, Republicans hope one of their candidates advances to the general election. If not, it could reduce Republican turnout in the fall, which would affect down-ballot races.
In Montana, where polls close at 10 p.m. EDT, the Republican primary will determine who will face Democratic Sen. Jon Tester, who is running for a third term in a state President Donald Trump won in 2016. There’s also a Democratic primary in the at-large congressional district to determine who will challenge GOP Rep. Greg Gianforte.
Alabama, Iowa, Mississippi, New Jersey, New Mexico and South Dakota also have primary races today.
In Alabama, GOP Rep. Martha Roby is facing four fellow Republicans challenging her for her seat in the state’s 2nd District. Roby drew the ire of Trump’s supporters when she disavowed the Republican then-presidential nominee after the infamous 2005 “Access Hollywood” tape that captured him making lewd remarks about women was released a month before the election. If no candidate clears 50% of the vote tonight, the top two will advance to a runoff on July 17.
In South Dakota, Rep. Kristi Noem is running in the Republican primary for governor against Attorney General Marty Jackley. If Noem wins, she’d be on her way to becoming the state’s first female governor.
In Iowa, there’s a Democratic primary for governor, whose winner will have a shot at unseating Republican Gov. Kim Reynolds. In Iowa’s 3rd Congressional District, several Democrats are facing off to challenge Republican Rep. David Young in the fall. Here, all eyes are on Pete D’Alessandro, a former Bernie Sanders 2016 campaign staffer who received the support of his former boss. His performance tonight will be seen as a test of Sanders’ brand in the pivotal early presidential primary state.