If Democrats have any chance of winning back the majority in the House of Representatives, they’ll have to make huge gains in the state of California.

California is undoubtedly a blue state, but it also has one of the largest GOP delegations in Congress, with 14 Republicans in the House. This year, Democrats are ambitiously aiming to flip 10 of those seats to blue. But it won’t be easy.

California has a “top two” primary system, meaning Republicans and Democrats run together in the primary and the first- and second-place candidates get to duke it out in the general. In other words, there’s always the possibility that one party could get shut out of the general election altogether.

Here are the nine districts to keep an eye on.

California’s Fourth District: Democrats are trying to target California’s most conservative Congress member

Who is the Republican? Rep. Tom McClintock is the incumbent Republican. He’s the most conservative Congress member in California and is serving his fifth term. He’s almost guaranteed the top spot in the top-two primary system.

Who are the Democrats? Two women, both in their 30s, stand out from the pack of four Democratic candidates. Jessica Morse, 35, a national security strategist, whose résumé includes the State Department, Defense Department, and USAID, has gained the Democratic Party endorsement, as well as the support of many progressive groups. She’s outraised her Democratic competitors and even Republican incumbent Rep. Tom McClintock and is the Democratic favorite. But Regina Bateson, a Roseville native and MIT professor on leave, has mounted a formidable challenge.

Here’s the kicker: Bateson said she’d drop out of the race if the party endorsed someone else — then didn’t. The other two candidates in the race are Roza Calderon, a 32-year-old geographic information systems consultant who has some grassroots support; and Robert Lawton, an investment adviser and rancher based in Yosemite, have raised significantly less.

What’s the story? This district is rated Likely Republican by the Cook Political Report, but Democrats still think it’s in play. McClintock represents a district encompassing Roseville, Lake Tahoe, and down to Yosemite National Park — but he doesn’t live there. This won’t be an easy race for Democrats. It’s an R+10 district. McClintock won reelection in 2016 by 25 points, and Donald Trump took the district by 16 points.

California’s 10th District: a beekeeper, the venture capitalist behind Blue Apron, and the daughter of immigrant farm workers

Who is the Republican? This is Rep. Jeff Denham’s district. He’s been in Congress since 2010, coming in on the Tea Party wave.

Who are the Democrats? Among the five Democrats on the ballot, three stand out: Michael Eggman, a 53-year-old third-generation beekeeper who is making his third run against Denham; Josh Harder, the 31-year-old venture capitalist who backed the meal kit service Blue Apron; and Virginia Madueño, the 52-year-old former mayor of Riverbank, who has been tapped by Emily’s List. The California Democratic Party hasn’t endorsed anyone, and all three are duking it out to prove their close ties to the district.

What’s the story? In 2016, Denham narrowly won by 3.4 percent in one of the closest House races in the country. Hillary Clinton won the district in 2016 by 3 points too; it’s rated a toss-up and is a prime pickup opportunity for Democrats. The Central Valley district, a strongly agricultural area, is 40 percent Hispanic. Denham has been scrambling — or at least he appears to be — on the forefront of a congressional push from moderate Republicans to force the House into an immigration debate. He’s pretty candid that he wants that debate to happen before the midterms.

California’s 22nd District: Devin Nunes has made quite a name for himself

Who is the Democrat? There’s one standout Democrat: Andrew Janz, the Fresno County deputy district attorney. He’s been endorsed by the California Democratic Party and has a $1.8 million war chest to go against Republican incumbent Rep. Devin Nunes. Two others, entrepreneur Bobby Bliatout and business consultant Ricardo Franco, are also running.

Who are the Republicans? Incumbent Rep. Devin Nunes has made quite a name for himself under Trump as the author of the House Intelligence Committee’s dubious Russia investigation memo. He’s been in Congress since 2013.

What’s the story? This won’t be an easy race for Democrats in November. The Fresno-area district is conservative and rated “Solid Republican.” But Democrats are still gunning for it because Nunes, the chair for the House Select Committee on Intelligence, is so well-known and hated for his role releasing the committee’s Russia investigation memo. He’s been a very pro-Trump figure, pushing the narrative that the FBI abused its powers while investigating Trump’s 2016 campaign. Nunes has supposedly recused himself from the investigation because of his close ties to Trump and his role on the president’s transition team.

California’s 25th District: a Republican in a Clinton and Obama district

Who is the Democrat? There will be four Democrats on the ballot. Eyes are on attorney Bryan Caforio, who lost in a high-profile and super-expensive race against incumbent Republican Rep. Steve Knight in 2016. He has locked up a lot of endorsements from labor and progressive groups. But nonprofit policy advocate Katie Hill is also running a competitive campaigns. Hill has the backing of Emily’s List, NARAL, Planned Parenthood, and a number of California’s Democratic Congress members. Caforio and Hill have both out-fundraised Knight so far.

Who are the Republicans? Rep. Steve Knight, the incumbent. He was elected to Congress in 2014. Before that, he served in the California legislature and worked for the Los Angeles Police Department.

What’s the story? This district, which covers the region north and northeast of Los Angeles, is a key pickup opportunity for Democrats. It’s a toss-up, but Los Angeles County is trending increasingly liberal, and for a Republican district, it’s firmly anti-Trump. Clinton carried the district by 7 points, and Knight outperformed Trump in the district by nearly 10 points in 2016. Barack Obama won the district in 2008, but it went for Mitt Romney in 2012.

Knight has had to walk a fine line under Trump. But he’s largely stayed in line with GOP leadership, voting with Republicans to repeal Obamacare and pass massive GOP tax cuts. He’s strayed a little on immigration, signing on to a discharge petition to force a debate in the House, like many of his fellow vulnerable California Republicans.

California’s 39th District: in an open district, Democrats are in a squabbling match

Who are the Democrats? In a packed field of six Democrats, two wealthy candidates are in an ugly battle for a spot on the November ballot. Gil Cisneros, a former Navy officer and 2010 lottery winner (he won $266 million) is on the DCCC’s Red to Blue list, which is as close as the national campaign arm gets to endorsing a candidate. He’s up against Andy Thorburn, a health insurance executive and former teacher.

It’s been a doozy of a race, including allegations of tax fraud and legal action over a voicemail. Cisneros is claiming Thorburn released a “fabricated” voice message in which a voice sounding like Cisneros warns Thorburn he’s going to go negative. There’s also another Democrat in the running, pediatrician, Mai Khanh Tran, who’s been endorsed by Emily’s List.

Who are the Republicans? The field of Republicans running in this race is just as deep as the Democratic side. Three stand out: Shawn Nelson, the Orange County supervisor; Bob Huff, who is the former state Senate minority leader; and Young Kim, who has served in the state Assembly.

What’s the story? This is an open seat, currently held by retiring Republican Rep. Ed Royce, which makes it all the more attractive for Democrats in a blue year. The district, which is anchored in Orange County and covers Fullerton and Yorba Linda, is a total toss-up. Cook says it leans Democratic. But Democrats have failed to coalesce behind a single candidate, and the race has devolved into a negative squabbling match that could result in Democrats getting shut out of the general election.

California’s 45th District: an embattled incumbent who may have stuck too close to the Republican agenda

Who are the Democrats? There are four Democrats all vying for a second-place spot to run in November. Two UC Irvine law professors: Katie Porter, a progressive who has Sens. Elizabeth Warren and Kamala Harris on her side; and the more moderate Dave Min, who received the California Democratic Party’s endorsement. There there’s Brian Forde, an ex-Republican who worked under President Obama, and Kia Hamadanchy, a young Iranian-American Democratic populist who worked under Sherrod Brown.

Who is the Republican? Incumbent Rep. Mimi Walters, who came into Congress in 2014.

What’s the story? This district has never gone blue, but Clinton beat Trump by 5 points in 2016, and the Cook Political Report rates the race as Lean Republican. Walters, who did run substantially ahead of Trump in the district, has stuck with the Republican agenda; she voted for Obamacare repeal and the tax bill, both of which particularly hurt California.

It’s 60 percent white, 21 percent Asian-American, 14 percent Latino. And while Orange County has long been a conservative stronghold, the changing landscape of this district could flip it.

California’s 48th District: a drunken bar fight, a Putin-adored Republican, and a Kasich-friendly Democrat ... what could go wrong?

Who are the Democrats? There are eight Democrats on the ballot, but two are in serious contention for a spot on the ballot in November. There’s Harley Rouda, the DCCC- and Indivisible-endorsed real estate investor and ex-Republican; and Hans Keirstead, a stem cell scientist with a California Democratic Party endorsement who has spent a lot of time trying to fend off 2009 allegations that he slept with his grad students and got into a drunken fistfight. These two are tied in the polls, but there are others still in the race who could split the vote count even more.

Who are the Republicans? Rep. Dana Rohrabacher is the incumbent. He’s represented this district for 30 years and isn’t too popular. Well, Vladimir Putin really likes him, and the feeling appears to be mutual; Rohrabacher, in addition to being a climate change skeptic and okay with housing discrimination against LGBTQ people, is also super pro-Russia.

He’s so unpopular that he’s getting challenged by Scott Baugh, a former Orange County Republican Party chair who (fun fact) is a longtime friend of Rohrabacher’s. In the 1990s, Rohrabacher’s wife pleaded guilty to two felony charges for recruiting and installing a decoy Democratic candidate to split the vote and get Baugh elected to the California Assembly.

What’s the story? In short, this race is a circus. Clinton eked out a 1-point win in this district in 2016, so Democrats are highly energized to take it over. On top of that, Rohrabacher, who has represented the area — a 40-mile coastal stretch of Orange County — for 30 years, is pretty unpopular.

But that energy to kick Rohrabacher out of office has been a Catch-22 for Democrats. He attracted a pretty formidable Republican challenger who is now neck and neck with the top two Democrats in the race. Not to mention that there will be a total of 16 names on the ballot, almost half of whom have unofficially dropped out of the running but are still likely to get some uninformed votes.

There’s a big possibility Democrats are going to get shut out of this race altogether, which, needless to say, would be a major upset in a year they’re trying to take back control of the House.

California’s 49th District: a Democratic shutout is just as likely as a Republican one

Who are the Democrats? There are four Democrats to keep an eye on: real estate investor Paul Kerr; Sara Jacobs, who is the CEO of a nonprofit and from a wealthy family; environmental lawyer Mike Levin; and retired Marine Col. Doug Applegate. No one seems to be taking a clear lead in what has become a very heated and expensive race.

Who are the Republicans? There are a whopping eight Republicans on the ballot, and no clear winner among the pack either. Among the notable candidates are Rocky Chávez, a state Assembly member and retired Marine Corps. colonel; Diane Harkey, who used to serve in the state Assembly and has current Rep. Darrell Issa’s endorsement; Kristin Gaspar, an Orange County supervisor and small-business owner who has Rep. Ed Royce’s endorsement; and Craig Nordal, a real estate investor who said he’d join the conservative Freedom Caucus if elected.

What’s the story? Issa was considered to be the most vulnerable Republican in the 2018 midterm cycle, winning reelection by the slimmest margin in the country — then he dropped out. It’s left his Orange County/San Diego County district up for grabs. This is an R+1 district that Democrats have a huge chance of taking if they can get on the ballot in November. Clinton won by 7.5 points, and with such a stacked ballot on both sides of the aisle, the possibility of a Republican shutout is just as likely.

California’s 50th District: incumbent Duncan Hunter is being investigated by the FBI for campaign fraud

Who are the Democrats? There are two formidable Democratic challengers: retired Navy SEAL Josh Butner and Ammar Campa-Najjar, who worked in Obama’s Department of Labor. Realtor Patrick Malloy, who has run against Hunter in the past, is also in the race.

Who are the Republicans? Rep. Duncan Hunter is running as the incumbent. He’s an Iraq and Afghanistan war veteran and was elected to Congress in 2008. In Washington, he’s been dogged by ethical and legal complaints. He’s being challenged by El Cajon Mayor Bill Wells and business executive Shamus Sayed.

What’s the story? The district alone is hardly competitive. Covering most of San Diego County, it’s an R+11 suburban district that’s extremely white. Registered Republicans outnumber registered Democrats 42 percent to 27 percent, and Trump won by 15 points; 25 percent have no party preference. The demographics here have been changing slowly; there’s a growing Latino population, and Democrats think they can shift the area’s politics.

Plus, Hunter has been dogged by serious legal and ethics scandals. He’s been accused of having inappropriate relationships with women, drinking on the job, and other unprofessional conduct, all of which his office has denied. Then there are his financial woes. The FBI is investigating allegations that he used campaign funds for personal use, like private school tuition, vacations, and oral surgery. He’s also undergoing a House Ethics Committee investigation.

It’s likely this district will remain in Republican hands, but that doesn’t mean Hunter isn’t in trouble. Even his Republican colleagues were reportedly encouraging him to drop out.

Ella Nilsen and Dylan Scott contributed to this report.