The 2016 presidential election margin in a particular state can serve as a useful indicator of how the parties might perform for governor, particularly when there is no incumbent running. However, voters who supported one party for president are often more likely to split their ticket for the opposite party in state elections than in federal races.

The map below demonstrates just how imperiled some of these Republican governorships could be if Trump sparks a downballot backlash. Nine of the 27 states where the GOP is playing defense voted for Hillary Clinton, five of those by double-digit margins. Another five states backed Obama in 2012, and two (Georgia and Arizona) went for Trump by about 5 points or less.

Republicans could be in serious danger of losing highly populous states such as Florida, Illinois, Michigan, Ohio, New Jersey, and Wisconsin even in a relatively typical midterm environment. If the 2018 elections turn into a true Democratic wave scenario along the lines of what we saw in 2006, it might even wash Republicans out to sea in redder states like Georgia and Arizona

Such gains could dramatically reshape the current partisan landscape in state governments as a whole. The map below shows all the states where one party controls both legislative chambers and the governor’s office, also known as a “trifecta.”

Republicans have total control over 25 states outright and another two where they can override a Democratic governor’s vetoes; these 27 states cover 56 percent of the population. Meanwhile, Democrats have full controlin a mere six states and veto-proof majorities to override a Republican governor in just two more. These eight Democratic-controlled states add up to only 19 percent of the population, or roughly one-third as much as Republicans govern.

Consequently, gaining the governor’s office, and with it the veto pen, is often the most effective way that Democrats can break up the unified grip Republicans have on many state governments like Florida, Michigan, and Wisconsin. That’s especially true since many of these states have Republican gerrymanders that make winning legislative majorities more difficult for Democrats than a statewide gubernatorial race.

Let’s take a look at some of the top Democratic targets individually.

Florida

Democrats painfully fell just 1 point shy of winning the Sunshine State in both 2010 and 2014 even though the national environment favored Republicans both years. They hope that an open-seat race to succeed term-limited Gov. Rick Scott will see their fortunes change in 2018 despite Trump’s narrow 49-47 victory in Florida. A Democratic victory would give them a veto over the Republicans’ legislative majority, which isn’t likely to go away any time soon.

Tallahassee Mayor Andrew Gillum and wealthy real estate company owner Chris King have already joined the Democratic field, while ex-Rep. Gwen Graham and wealthy Miami Beach Mayor Philip Levine have both signaled that they’re planning to run, and several other Democrats are still considering. State Agriculture Secretary Adam Putnam hasn’t announced yet, but he appears to be the frontrunner for the Republicans, although many others could end up running too. Scott in particular is reportedly unhappy with the developing GOP field and appears to be trying to recruit a rich self-funder like himself to get in.

Illinois

GOP Gov. Bruce Rauner just narrowly won in 2014 due to the Republican wave and Democratic incumbent Pat Quinn’s deep unpopularity. Thanks in part to his push for anti-worker policies causing a protracted budget battle with the Democratic legislature, Rauner has become deeply unpopular himself in a state that Clinton carried 55-38. And beating Rauner would allow Democrats to regain unified control over state government once again.

Rauner’s ability to self-fund his campaign means that he won’t be a pushover: He’s reportedly worth $1 billion and has already devoted $50 million to his re-election bid. However, Democrats smell blood in the water. Businessman Chris Kennedy, the son of late Sen. Robert F. Kennedy, is already in, and he likely can do some self-funding of his own. A number of other prospective candidates are also eyeing the race.

Kansas

Kansas has long been one of America’s most reliably red states, and Trump easily carried it 56-36 last year. However, Gov. Sam Brownback’s radical tax cuts for the rich eviscerated the state’s finances, leading to stark cuts to education funding and sparking an angry backlash. The 2014 GOP wave allowed Brownback to pull off a 50-46 win over then-state House Minority Paul Davis, but Kansas’ financial situation remains bleak. Brownback faces term limits in 2018, but Democrats still hope to tie the Republican nominee to the nation’s arguably least popular governor.

Former Wichita Mayor Carl Brewer has already entered the Democratic primary, while Davis is considering a second bid. Undeterred by Brownback’s legacy, several top Republicans, such as Lt. Gov. Jeff Colyer and voter suppression-crusading Secretary of State Kris Kobach, are also considering running. Should Democrats win the governor’s race, Democratic legislators could form a coalition with more moderate Republicans to help undo Brownback’s damage.

Maine

Maine has voted Democratic in every presidential race since 1992, but Clinton’s 48-45 victory was far slimmer than Obama’s 56-41 win in 2012. Democrats are still sanguine that they can succeed term-limited Gov. Paul LePage, who won with a mere plurality in both 2010 and 2014 after Democrats and left-leaning independents split the the vote. Many prominent Democrats are considering running, but the biggest wildcard is likely popular Republican Sen. Susan Collins, who hasn’t ruled out a bid. A Democratic victory might give Team Blue unified control depending on 2018’s legislative elections.

Fortunately for Democrats, divided opposition is far less likely to aid Republicans in 2018, since Maine voted to adopt instant-runoff voting in a ballot initiative last yearm although this new system still has to survive judicial review first. If it does, voters would rank multiple candidates in order of preference. If no one attains a majority in the first round, the last-place candidate gets eliminated, and votes for that candidate shift to each voter’s second preference. That process repeats until one candidate achieves a majority, making it highly unlikely for an extremist to win with just 38 percent like LePage did in 2010.

Maryland

Clinton won Maryland by a huge 60-34 margin, but a combination of 2014’s Republican wave and outgoing Democratic Gov. Martin O’Malley’s unpopular policies helped Republican Larry Hogan pull off a surprising 51-47 win. The governor has long had a stellar approval rating, but Trump’s deep unpopularity in this dark blue state might cause voters to revert back to their partisan preferences. Democrats also hope that Hogan will have a tough time distancing himself enough from Trump to keep left-leaning voters happy while keeping his own base content.

Both Prince George's County Executive Rushern Baker and Baltimore County Executive Kevin Kamenetz are considering running for the Democratic nod, as is former NAACP President Ben Jealous. Democrats nominally have enough seats in the legislature to over-ride Hogan’s vetoes, but regaining the governor’s office would allow many more progressive measures to pass with a simple majority, rather than relying on the support of more moderate Democrats to provide a supermajority.

Massachusetts

Just like Maryland, Massachusetts is a deep blue state that saw Republicans eke out an upset victory for an open seat in the 2014 wave against a flawed Democratic nominee. Republican Gov. Charlie Baker has also boasted a sky-high approval rating even though Clinton won Massachusetts by a similar 60-33 spread. Just like in Maryland, Massachusetts Democrats also have nominally veto-proof legislative majorities, but that’s in large part a consequence of having many moderate Democrats who might not vote to override vetoes of more progressive measures.

Democrats aren’t as optimistic about their chances here compared to states without popular incumbents, but they’re holding out hope that Trump will weigh down Baker. Ex-state Budget Chief Jay Gonzalez is already in and Newton Mayor Setti Warren is a likely candidate, while wealthy former state Sen. Dan Wolf hasn’t ruled out running. Attorney General Maura Healey hasn’t quite shut the door on a bid either, though she’s repeatedly insisted she wants to seek re-election instead.

Michigan

Michigan was the closest state for president in 2016, favoring Trump by just 0.2 percent after having previously supported every Democratic nominee since 1992. Gov. Rick Snyder only won re-election by 51-47 during the Republican year of 2014, and Democrats are eager to capitalize on the term-limited governor’s unpopularity, stemming partly from the fallout of his disastrous handling of Flint’s water crisis.

State Attorney General Bill Schuette and Lt. Gov. Brian Calley are likely candidates for Republicans, while a few others are considering. On the Democratic side, former state Senate Minority Leader Gretchen Whitmer is running; ex-Detroit Health Director Abdul El-Sayed also recently jumped in, though he looks like a longshot to win the primary. Flint-area Rep. Dan Kildee is also considering a bid. A Democratic victory would break the Republican legislative trifecta, giving Team Blue the all-important veto pen.

Nevada

Republican Gov. Brian Sandoval, who passes for a moderate in today’s GOP, faces term limits in 2018, and Democrats hope Clinton’s 48-46 victory plus the fact that Team Blue regained both legislative chambers in 2016 are signs they can win. If Democrats prevail in 2018 and maintain their legislative majorities, they would win unified control over state government for the first time in over a quarter century.

The Republican field has begun consolidating around state Attorney General Adam Laxalt, a hard-right true believer who would have a hard time recreating Sandoval’s bipartisan appeal and only won his current office in a fluke upset thanks to the 2014 wave. The Democratic field has been slow to develop, but wealthy businessman Stephen Cloobeck reportedly said he would run back in January. Clark County Commissioner Steve Sisolak is also talking about getting in, while state Senate Majority Leader Aaron Ford hasn’t ruled it out either.

New Hampshire

Republicans just narrowly won complete control over New Hampshire’s state government in 2016, with Chris Sununu winning the open governor’s race 49-47. At the same time, Democrats swept all of the state’s federal races, with Clinton prevailing 47-46. The Granite State is one of just two states along with Vermont that gives its governors two-year terms, so Sununu faces re-election in 2018.

Democrats have a deep bench of potential challengers from Congress, the legislature, or the powerful five-member Executive Council, of which both parties’ 2016 nominees were members at the time. Given its swingy and closely divided nature, either party could potentially win complete control over New Hampshire’s state government depending on the way the winds blow in 2018. However, New Hampshire has been reluctant to fire governors after just two years. Aside from Republican Craig Benson’s narrow 2004 defeat, no first-term governor has lost re-election since 1926.

New Jersey

The Garden State is the only state where the GOP will be on defense in 2017, but if presidential performance and the incumbent governor’s popularity rule the day, then Republicans will have a very tough time preventing Democrats from regaining unified control over the state government. Trump lost New Jersey by 55-41, and Gov. Chris Christie is in contention for America’s most detested governor, with an approval rating scraping just 20 points in recent polls.

Christie’s unpopularity hasn’t stopped his lieutenant governor, Kim Guadagno, from entering the race, though she’s hoping that her publicly fractured relationship with Christie will help her in a general election. Assemblyman Jack Ciattarelli is also running, while ex-Saturday Night Live cast member Joe Piscopo continues to amuse us by flirting with a bid. On the Democratic side, former Goldman Sachs executive Phil Murphy has vacuumed up much of the establishment’s support, while state Sen. Ray Lesniak is also a contender, and Assemblyman John Wisniewski is running as a Bernie Sanders devotee.

New Mexico

New Mexico is a Democratic-leaning state that favored Clinton by a solid 48-40 margin, and Republican Gov. Susana Martinez will face term limits in 2018, giving Democrats a prime pickup opportunity to regain unified government after they won back control of the legislature in 2016. Democratic Rep. Michelle Lujan Grisham, whose Albuquerque district covers one-third of the state, has been the only major candidate from either party to enter the race, but several other prominent Democrats and a few Republicans are also considering running.

Ohio

For the longest time, the Buckeye State was the nation’s quintessential bellwether, but Ohio veered sharply to the right in 2016 when it favored Trump 51-43. Republican Gov. John Kasich is well-liked, but fortunately for Democrats, he’s term-limited in 2018. Republicans currently have veto-proof majorities in the state House and Senate, so a Democratic governor would need to hope their coattails carry a few legislators into office, too. It remains to be seen whether Trump’s dominant victory was a durable shift or if Ohio will bounce back toward the center, but several candidates from both major parties are mulling the race regardless.

The Republican field has so far seen state Attorney General Mike DeWine and Lt. Gov. Mary Taylor already announce bids, while Secretary of State Jon Husted and Rep. Jim Renacci are also potential candidates. For Democrats, former Rep. Betty Sutton and state Senate Minority Leader Joe Schiavoni recently joined the race, while many other prominent party members could jump in too.

Vermont

Clinton’s 57-30 victory makes Vermont the state where Trump won his second-lowest share of the vote, but the Green Mountain State also has a strong independent streak. Thanks in part to an unpopular outgoing Democratic governor, then-Lt. Gov. Phil Scott won the open 2016 gubernatorial race by a decisive 53-44 margin. Vermont is the only state besides New Hampshire to elect its governor every two years, so Scott will face re-election in 2018, but he could be very tough to beat.

So far few Democrats have made any noise about challenging him, but the party dominates throughout the rest of the state government, giving them a very deep bench. If they prevail, they would once again assume unified power in Vermont.

Wisconsin

Trump’s shocking 47-46 Badger State victory made him the first Republican to carry Wisconsin’s electoral votes since the 1984 Reagan landslide, but Democrats will likely gun hard break the GOP’s complete grip on state government here. Republican Gov. Scott Walker has long been a national bogeyman for progressives thanks to his assault on workers’ rights and public education, and so far, he’s hinted that he might run for a third term rather than step aside in 2018.

However, even if Walker does seek re-election, he might have worn out his welcome with Wisconsin voters. Polling in 2016 consistently gave the governor weak approval ratings, and voters might be ready for change after eight years of GOP control. Still, Walker is a national conservative idol with a massive national fundraising network, and the well-funded incumbent won’t be easy to beat. The Democratic field has been slow to take shape, but a handful of state legislators and even perennially talked-up Rep. Ron Kind are potential contenders.

In total, Democrats could gain monumental gubernatorial victories if the 2018 national environment favors them as a backlash to Trump. Success could give them total control over government in highly populated states like Illinois and break the Republican chokehold on big states like Florida and Michigan.

These gains come with the bonus of being the elections that will determine control over 2020s redistricting, meaning Democratic advances in 2018 won’t just shape legislation for the next four years, but could move policy to the left at both the federal and state level for more than a decade to come.