Democrats are favored to win back the House on November 6 — but it’s no sure bet.

They need to pick up 24 seats to win back the House. Buoyed by the backlash against President Donald Trump and the anger of women voters, House Democrats are eyeing pickup opportunities all around the country.

The prediction of a blue wave, coupled with constant House ratings changes from election watchers, can make it hard to keep up with a dizzying number of House races. So we tried to distill it down to the most important — and interesting — races of 2018. You’ll notice they’re all open seats or endangered Republican incumbents. That’s in part because of the lopsided playing field this year to retake the House. There are just many, many more pickup opportunities for Democrats.

At the end of the day, it will come down to a handful of closely contested races. They include key districts that Democrats need to win in order to take back the House, but many of these races speak to some of the larger themes playing out between Republicans and Democrats across the country.

Here are the 16 most interesting House races we’re watching.

Iowa’s Fourth Congressional District: Rep. Steve King vs. J.D. Scholten

Who is the Republican? Rep. Steve King, in office since 2003. He voted for ACA repeal and the GOP tax cuts. He’s also notorious for his openly racist rhetoric and support for neo-Nazi politicians in Europe and Canada.

Who is the Democrat? J.D. Scholten, a former baseball player and paralegal.

What’s the playing field? Cook rates the race Lean Republican.

What’s interesting about this race? Republicans on Capitol Hill have been looking the other way for years as King spouts racist rhetoric. But it may finally be catching up with him. The breaking point appears to have come after the deadly mass shooting at a synagogue in Pittsburgh that killed 11 Jewish worshippers and was believed to be motivated by anti-Semitism. That, combined with King recently meeting with a far-right Austrian party while he was on a trip to Europe to see Holocaust memorial sites, has Republicans stepping away from the lawmaker.

The trip was funded by a Holocaust memorial group, so King’s meeting with a party that has ties to neo-Nazis sparked outrage. In the wake of the backlash, National Republican Congressional Committee Chair Rep. Steve Stivers (R-OH) released a statement condemning King’s words and actions, and King is losing financial support (he’s already very low on cash).

What does the polling say? King has been ahead in every poll so far, but a new poll from Change Research showed Scholten within a single point of the incumbent. Of course, this is just one poll. But that combined with the fact King is just now putting a TV spot up compared to Scholten’s aggressive TV presence and campaign could be troublesome for him. A New York Times/Siena College poll has King up by 5 points.

California’s 45th Congressional District: Rep. Mimi Walters vs. Katie Porter

Who is the Republican? Incumbent Rep. Mimi Walters, first elected in 2014. She voted for Obamacare repeal and the tax bill, which hurt California by eliminating the federal income tax deductions for state and local taxes.

Who is the Democrat? UC Irvine law professor Katie Porter, who is running on Medicare-for-all. Porter has the support of progressive groups and Sens. Elizabeth Warren (D-MA) and Kamala Harris (D-CA).

What’s the playing field? The nonpartisan Cook Political Report rates this race a toss-up.

What’s interesting about this race? Porter is running an unabashedly progressive campaign. Walters also voted for the Republican tax bill that’s likely going to increase taxes for lots of voters in this district. Meanwhile, the city of Irvine and other areas in Orange County making up the district have a lot of conservative DNA (they’ve never sent a Democrat to Congress), but the area is highly educated and diversifying rapidly. Porter’s candidacy is a test of whether Democrats can run on a decidedly left-wing message and win, rather than running centrist candidates in moderate districts.

What does the polling say? It’s definitely a close race, but there are some good signs for Porter. The most recent New York Times/Siena College poll has her with a 2-point lead; another one from GBA Strategies showed her with a 1-point lead.

West Virginia’s Third Congressional District: Carol Miller vs. Richard Ojeda

Who is the Republican? Carol Miller, a West Virginia state delegate and bison farmer. (Republican incumbent Rep. Evan Jenkins unsuccessfully ran for Senate in 2018, losing his primary.)

Who is the Democrat? Richard Ojeda, a state senator and Army veteran who served in Iraq and Afghanistan. He voted for Trump in 2016 (something he later said he regretted), and rose to prominence during the West Virginia teachers strikes as a vocal advocate for raising teacher pay.

What’s the playing field? Cook rates it as Lean Republican. But it’s also worth noting that Rep. Nick Rahall (D) held the district from 1993 to 2015.

What’s interesting about this race? This is a true test of whether Democrats can chip away at Republicans’ hold on poorer Rust Belt districts that went overwhelmingly for the president in 2016. Trump won West Virginia by one of the biggest margins in the country, but technically, there are more registered Democrats than Republicans. The state has always had a populist streak, but political winds have shifted to the conservative side of late — especially as coal jobs have left and the economy has tanked. It’s also a test of whether more leftist populist ideas have sway in the state — Ojeda is for a public option and Medicare buy-in for health care.

What does the polling say? It’s a bit of a mixed bag. Ojeda appeared to be in the lead this summer, but Miller seems to have passed him in recent months. An October Monmouth poll found her with a 3-point lead, with the most recent NYT/Siena College September poll showing her 5 points ahead.

Kansas’s Third Congressional District: Rep. Kevin Yoder vs. Sharice Davids

Who is the Republican? Rep. Kevin Yoder, in office since 2011. Yoder voted for the GOP tax cuts and Obamacare repeal.

Who is the Democrat? Sharice Davids, an attorney and former mixed martial arts fighter. She’s Native American and openly LGBTQ.

What’s the playing field? Cook rates the race as Lean Democrat. Hillary Clinton narrowly won the district in 2016.

What’s interesting about this race? Yoder is one of the more endangered House Republicans in 2018. His suburban district, which includes part of Kansas City and its suburbs, is one Democrats actually have a decent shot at flipping (the district went for Clinton by 1 point in 2016). KS-03 and the neighboring Second Congressional District are key pickups for Democrats, and Davids is a young, dynamic candidate who represents the future of the party. Republicans are taking notice; the NRCC recently canceled a $1 million ad buy for Yoder, a sign he’s in trouble.

What does the polling say? Things are looking pretty good for Davids; the NYT/Siena poll had her 8 points ahead of Yoder, and an Emerson College poll had her 6 points ahead.

Kentucky’s Sixth Congressional District: Rep. Andy Barr vs. Amy McGrath

Who is the Republican? Rep. Andy Barr, in office since 2013. Voted for the GOP tax bill and Obamacare repeal.

Who is the Democrat? Amy McGrath, a Marine Corps veteran and the first woman to fly a combat mission for the Marines. She’s a political newcomer who beat the Democratic Congressional Campaign Committee’s initial favorite for the district in the primary and has proven herself to be a fundraising powerhouse.

What’s the playing field? Cook rates the race as a toss-up.

What’s interesting about this race? Similarly to West Virginia’s Third Congressional District, this Kentucky district is another test of whether a Democrat can win back Trump voters. There are more registered Democrats than Republicans here, and the district has a history of having representatives from both parties. But many counties in the Sixth overwhelmingly voted for Trump in 2016. McGrath wants to try to win them back by appealing to voters in rural areas, in addition to Democrats in Lexington, which is also in the district.

Barr has raised $4 million, but McGrath has outpaced that, hauling in more than $6 million largely from small donors. If she wins, Democrats may be looking at her to seek higher office, including the Senate, in coming years.

What does the polling say? The polling is spare, but it shows a very close race. Barr leads McGrath by about 1 point, well within the margin of error. The NYT/Siena poll has them tied.

Virginia’s 10th Congressional District: Rep. Barbara Comstock vs. Jennifer Wexton

Who is the Republican? Rep. Barbara Comstock, in office since 2015. She was swept into office in a 2014 Republican wave; now she might be swept out by a Democratic one.

Who is the Democrat? State Sen. Jennifer Wexton, an attorney.

What’s the playing field? Cook rates it as Lean Democrat.

What’s interesting about this race? Virginia’s 10th Congressional District is a suburb of Washington, DC. Clinton won it by 10 points in 2016, so it’s at the top of the districts Democrats think they can flip. Health care is sure to be a huge issue in the district, with Wexton able to run on the fact that Democrats expanded Medicaid in the state. Comstock voted against Obamacare repeal but for the individual mandate repeal in the GOP tax cut bill, which Democrats are hitting her on. The NRCC is spending on her race, but the conservative Congressional Leadership Fund PAC has been more hesitant to commit money — a sign of trouble.

What does the polling say? The polls look good for Wexton. She’s been in a comfortable lead recently; one Washington Post poll even showed her 12 points ahead Comstock, while the NYT/Siena poll shows her 7 points ahead. It could be closer, but Democrats have reason to be optimistic.

Virginia’s Seventh Congressional District: Rep. Dave Brat vs. Abigail Spanberger

Who is the Republican? Rep. Dave Brat, in office since 2015. You might remember him as the former college professor who beat then-House Majority Leader Eric Cantor in 2014. He voted for the GOP tax bill and Obamacare repeal.

Who is the Democrat? Abigail Spanberger, a former federal law enforcement officer and CIA operative.

What’s the playing field? Cook rates this race as a toss-up.

What’s interesting about this race? If you’re looking for an extremely conservative House Republican facing a credible Democratic challenger, Dave Brat is it. Brat is a member of the House Freedom Caucus — the super-conservative group of House Republicans that frequently challenges Republican leadership and pushes them to the right. Brat is trying to tie Spanberger to Nancy Pelosi (a name he evoked no less than 25 times in a single debate). A man who swept in during the age of the Tea Party, Brat could be toppled by a Democratic wave propelled by women. It may not help that he’s also running against a woman.

What does the polling say? A couple polls show the race as very close. The most recent NYT/Siena poll showed Brat with just a 2 point lead, but a Monmouth poll released on September 25 showed Spanberger in the lead, propelled by the district’s suburban voters.

Colorado’s Sixth Congressional District: Rep. Mike Coffman vs. Jason Crow

Who is the Republican? Rep. Mike Coffman, in office since 2009. He voted for GOP tax cuts and Obamacare repeal but has been outspoken against the Trump administration.

Who is the Democrat? Attorney and Army veteran Jason Crow.

What’s the playing field? Cook rates this race as Lean Democrat.

What’s interesting about this race? Democrats have been trying to unseat Coffman for years, but the moderate Republican has managed to hang on to his seat in this suburban Colorado district. Democrats are hitting Coffman on his votes for the tax bill and Obamacare repeal, as well as his donations from the National Rifle Association. The Sixth District is home to Aurora, the city where a gunman killed 12 people inside a movie theater in 2012. It’s also very close to Columbine High School, where the 1999 school shooting took place. Gun violence is personal in the area, and Crow has been openly running on gun control from the start of his campaign.

What does the polling say? The past few months have been good for Crow; Coffman’s last poll lead was back in the middle of summer, and recent polls show Crow with a comfortable lead. The latest NYT/Siena College poll showed Crow with a 11-point lead.

Illinois’s 14th Congressional District: Rep. Randy Hultgren vs. Lauren Underwood

Who is the Republican? Rep. Randy Hultgren, in office since 2011. He voted for GOP tax cuts and Obamacare repeal.

Who is the Democrat? Lauren Underwood, a registered nurse and former Obama administration adviser who helped implement the Affordable Care Act.

What’s the playing field? Cook rates the race as a toss-up.

What’s interesting about this race? Health care and the GOP bill to kill the Affordable Care Act loom large in this race. Hultgren voted for the Obamacare repeal bill after promising he wouldn’t support anything that weakened protections for preexisting conditions, and faced protests in his home district for the vote. The fact that Underwood was an adviser in President Obama’s Department Health and Human Services who helped implement the ACA makes this dynamic all the more interesting. Underwood, who is African-American and 32 years old, is attempting to unseat a white man in his 50s. The district voted for Trump by 4 points in 2016.

What does the polling say? There’s not a lot of polling, but the race is close. An earlier NYT/Siena College poll showed him 4 points ahead of Underwood among likely voters, but she’s since taken the lead by 6 points in a more recent NYT poll. That narrowed to just a 1-point lead among registered voters.

Minnesota’s Third Congressional District: Rep. Erik Paulsen vs. Dean Phillips

Who is the Republican? Rep. Erik Paulsen, in office since 2009. Paulsen voted for the GOP tax cuts and Obamacare repeal.

Who is the Democrat? Dean Phillips, a distillery CEO and philanthropist.

What’s the district rating? Cook rates this race as Lean Democrat.

What’s interesting about this race? Paulsen is considered a moderate Republican who didn’t support Trump in 2016, writing in Marco Rubio instead (Minnesota was the only primary state Rubio won). The Third Congressional District went for Hillary Clinton in 2016 but voted Paulsen in as well.

He’s taken some tough votes since then, sticking reliably with House Republicans on health care and taxes while also trying to separate himself from Trump. Phillips, the Democrat, is running on campaign finance reform. This is a bit ironic, as Phillips made a fortune off his family’s liquor business and gelato company. He has been upfront about his wealth, and vowed to run without self-funding his campaign or accepting PAC money, though he’s still getting plenty of money from various industries.

What does the polling say? Polling is looking good for Phillips; two polls released in early/mid-September had him leading Paulsen by double digits. A SurveyUSA poll released in late September showed the race narrowing, with Phillips in a 5-point lead. NYT/Siena has him 9 points ahead.

New York’s 19th Congressional District: Rep. John Faso vs. Antonio Delgado

Who is the Republican? Rep. John Faso, in office since 2017. He voted for Obamacare repeal but against the GOP tax bill, citing concerns about tax hikes in places with high state and local taxes.

Who is the Democrat? Antonio Delgado, an attorney and former Rhodes scholar.

What’s the playing field? Cook rates the race as a toss-up.

What’s interesting about this race? A number of things are at play in this Hudson Valley district. The main policy battle in the race is over health care; Delgado is hammering Faso for his vote to repeal the Affordable Care Act. Meanwhile, Faso is trying to paint Delgado’s health care platform (advocating for a Medicare public option but not a single-payer system) as radically to the left. Race has also become a flashpoint in the campaign, as Republicans have run ads juxtaposing old videos Delgado shot as rapper “AD the Voice” with his current campaign ads, arguing the lyrics should disqualify him from representing the district. It’s pure race-baiting in an overwhelmingly white district.

What does the polling say? This race is very close. Polls in mid/late August found Faso with a 5-point advantage, but a more recent Monmouth University poll found the two candidates are essentially tied, with Delgado in a 2-point lead. NYT/Siena has him ahead by just 1 point.

Texas’s Seventh Congressional District: Rep. John Culberson vs. Lizzie Pannill Fletcher

Who is the Republican? Rep. John Culberson, in office since 2001. He voted for the GOP tax cuts and Obamacare repeal.

Who is the Democrat? Lizzie Pannill Fletcher, a longtime attorney in Houston.

What’s the playing field? Cook rates the race as a toss-up.

What’s interesting about this race? The most interesting thing about this race is simply whether dislike of Trump and Democratic energy will mean Democrats can flip a Texas district that Culberson has had locked down for decades. The district went for Clinton in 2016. Democrats have been dreaming of turning Texas purple for years, and they have a decent shot in the Seventh District, which is mostly suburbs of Houston.

In addition to health care, Pannill Fletcher is hitting Culberson on issues including disaster relief and infrastructure funding for Houston (remember that the city was badly flooded by Hurricane Harvey and has very little public transportation). She’s also talking a lot about women’s issues, including reproductive rights.

What does the polling say? Culberson and Fletcher are battling in a close race. The NYT/Siena College poll in mid-September showed Culberson up by 3 points, a lead that’s since narrowed to 1 point. A Public Policy Polling survey around the same time showed Fletcher ahead by 2 points.

Nebraska’s Second Congressional District: Rep. Don Bacon vs. Kara Eastman

Who is the Republican? Rep. Don Bacon is a freshman. Bacon voted for Obamacare repeal and the GOP tax cuts.

Who is the Democrat? Kara Eastman, president of a local health care nonprofit and a supporter of Medicare-for-all.

What’s the playing field? Cook rates the race as Lean Republican.

What’s interesting about this race? Eastman made waves earlier this year when she beat the DCCC’s preferred candidate, former Rep. Brad Ashford (Ashford was previously a Republican but most recently served as a Democrat, and Bacon beat him in 2016). Eastman was notably more progressive than Ashford, backing Medicare-for-all, and with her win, Democratic voters in the district sent a message that they wanted someone who could draw a real contrast with Bacon. National Democrats are somewhat worried that running a more liberal candidate against Bacon will result in a loss in the district, but it’s an interesting test of whether progressive ideas can prevail in a swing district in the Midwestern plains.

What does the polling say? Bacon seems to have a pretty clear advantage over Eastman. The latest NYT/Siena College poll found him 9 points ahead of her. Other polls show his advantage closer to 5 points, but Eastman hasn’t been able to capture a lead yet.

Pennsylvania’s First Congressional District: Rep. Brian Fitzpatrick vs. Scott Wallace

Who is the Republican? Rep. Brian Fitzpatrick, a former FBI agent, is also a freshman. He voted for the GOP tax cuts but against Obamacare repeal.

Who is the Democrat? Attorney Scott Wallace, who is self-funding his campaign.

What’s the playing field? Cook rates the race a toss-up.

What’s interesting about this race? Pennsylvania is interesting for the sheer number of important, contested House seats it contains; the Keystone State has nine races that Cook lists as competitive. Granted, some are more competitive than others, given the state’s recent redistricting that makes Pennsylvania’s electoral map fairer for Democrats.

Flipping Fitzpatrick’s seat is an important ingredient of this strategy, given that Clinton narrowly won it in 2016. Wallace, a deep-pocketed Democrat, is running on a platform including Medicare-for-all and green jobs. Fitzpatrick could be tough to beat, though; Democrats are hitting him on his tax bill vote, but he bucked Republicans by opposing Obamacare repeal.

What does the polling say? Another close race. Fitzpatrick has been in the lead most summer and fall, but one NYT/Siena College poll showed Wallace with a 7-point lead. The most recent NYT/Siena poll, however, had Fitzpatrick back in a 1-point lead.

Ohio’s First Congressional District: Rep. Steve Chabot vs. Aftab Pureval

Who is the Republican? Longtime Rep. Steve Chabot, who was in office from 1995 to 2009, briefly unseated for two years, and then reelected in 2011. He voted for Obamacare repeal and the GOP tax cuts.

Who is the Democrat? Aftab Pureval, who currently serves as the Hamilton County clerk of courts.

What’s the playing field? Cook rates the race a toss-up.

What’s interesting about this race? Chabot has been in office for a very long time but was beaten by a Democrat in 2008 ... and then won reelection two years later. Now, there’s a lot of attention on this suburban Cincinnati district because Democrats need to win it (and others like it) to take back the House. Pureval is hitting Chabot on his votes on Obamacare repeal and taxes. The Democrat is fundraising a lot but also faces questions about whether he used money from his clerk of courts campaign on his race for Congress.

What does the polling say? The polls are looking pretty solid for Chabot. Despite one September poll showing Pureval with a 2-point lead, Chabot has been ahead consistently. The most recent poll from NYT/Siena College had him up by 9 points.

Florida’s 26th Congressional District: Rep. Carlos Curbelo vs. Debbie Mucarsel-Powell

Who is the Republican? Rep. Carlos Curbelo, in office since 2015. He voted for Obamacare repeal and the GOP tax bill (he helped draft the latter).

Who is the Democrat? Debbie Mucarsel-Powell, who works in nonprofits.

What’s the playing field? Cook rates the race a toss-up.

What’s interesting about this race? Curbelo is a moderate Republican in a very Democratic-leaning district. FL-26 went for Clinton by 16 points in 2016, and voted for Obama before that. Still, Curbelo has managed to hang on by positioning himself as a moderate Republican, especially on issues like immigration (he’s also one of the few Republicans to propose a carbon tax bill). He was one of the House GOP members who tried a last-ditch effort to force Republican leadership to take up a narrow immigration bill with the aim of finding a fix for the young unauthorized immigrants known as DREAMers, but the effort failed. Given his district is about 70 percent Hispanic, immigration is a pivotal issue for Curbelo. Mucarsel-Powell has been hitting him on his health care vote, in particular.

What does the polling say? This race looked like Curbelo’s to lose this summer, but now it’s neck and neck. Some of the recent polling has had Curbelo in a less-than-a-point lead, or just over 1 point ahead of his challenger. The most recent NYT/Siena College poll gives Mucarsel-Powell a 1-point lead.

Correction: An earlier version of this article said Iowa Democrat JD Scholten was a basketball player. He was a baseball player.