If there’s an abiding lesson from 2016, it’s that national public opinion in the presidential race is not as important as the votes of individual states. Republican Donald Trump won by taking 304 electoral votes to Democratic nominee Hillary Clinton’s 227, even as Clinton beat him by 2.9 million votes and 2.1 percentage points nationally.

In 2020, Democrats will be looking to recapture states Trump won that went for Democrat Barack Obama in 2008 and 2012. And many of those states will also be prime battlegrounds in the fight for control of the Senate, where Democrats need a net gain of four seats to take a majority (three if they win the White House and the vice president can break 50-50 ties), while Republicans need a net gain of 19 seats to retake the House.

A look at Texas, the most competitive state in the West, is below. These links will take you to the most competitive states in the East, the Midwest and the South.

Texas

Democrats have long been optimistic that the once reliably red Texas was moving in their direction, and they think they may have a shot at turning it blue in 2020. Republicans acknowledge the Lone Star State is becoming more competitive, but say Democrats still have a long way to go.

Texas presents a large prize in the presidential race: 38 electoral votes, the second-most of any state after California. Trump carried Texas by 9 points in 2016, but that was the smallest margin of victory for a GOP presidential nominee in Texas in 20 years. Former Housing and Urban Development Secretary Julián Castro is vying for the Democratic nomination, but is far behind leaders of the pack in national and early-state polls.

The state’s increasing competitiveness is due in part to its diversifying population, since people of color are more likely to support Democrats. The Census Bureau data put the state’s Hispanic population at nearly 40 percent. Trump is also struggling to win over higher-educated and wealthier voters in the suburbs. Immigration will likely continue to be a top issue for voters in the border state.

[The 10 most vulnerable House and Senate members up in 2020]

Democrats saw the 2018 results as a sign that Texas could be shifting to the left, particularly when it comes to congressional races. Then-Rep. Beto O’Rourke raised an eye-popping $80 million and came within 3 points of unseating Republican Sen. Ted Cruz. Democrats also flipped two GOP-held suburban House seats that Clinton won in 2016. Colin Allred, a former professional football player who worked in the Obama administration, defeated GOP Rep. Pete Sessions in the 32th District in suburban Dallas. And lawyer Lizzie Fletcher unseated GOP Rep. John Culberson in the Houston-area 7th District.

In 2018, six House Republicans won reelection by 5 points or less, and Democrats are targeting all of those seats this cycle. O’Rourke carried three of them: the 10th District, held by GOP Rep. Michael McCaul; the 23rd District, an open-seat race now that Rep. Will Hurd is retiring; and the 24th District, also an open seat with Rep. Kenny Marchant retiring.

O’Rourke narrowly lost the other three Republican-held districts. In the 21st District, GOP Rep. Chip Roy is running against former Democratic state Sen. Wendy Davis, who got national attention in 2013 when a floor speech she made in favor of abortion rights went viral. The 22nd District is now an open-seat race since GOP Rep. Pete Olson is retiring. GOP Rep. John Carter also won a close reelection in the 31st District against Air Force veteran MJ Hegar, who benefited from a viral campaign video. Hegar is now running for Senate.

Democrats are bullish about their chances to pick up House seats in Texas, with the Democratic Congressional Campaign Committee opening a southern headquarters there. Democrats have also branded a string of GOP retirements as a “Texodus,” saying it shows Republicans don’t want to face competitive races. Of their six targets, three are now open-seat races. Three other Republicans in safer GOP territory are also heading for the exits.

[A year out, here’s four scenarios for how 2020 could go]

Republicans dismiss their opponents’ enthusiasm about the state as Democrats misreading the 2018 results. They say the results were due to a unique amount of enthusiasm around a dynamic and well-funded Senate candidate in O’Rourke, which can’t be easily replicated. They also say that traditionally Republican voters in suburban areas who are unhappy with Trump could vote against him but support GOP candidates in down-ballot races.

Attention and organizing for competitive House races could affect the Senate race in Texas, where GOP incumbent John Cornyn is running for a fourth term. A crowded and diverse field of Democrats is competing to take on Cornyn, and it includes Hegar, who has been the top Democratic fundraiser so far. The other top fundraisers, according to Federal Election Commission reports, include Houston City Council member Amanda Edwards, state Sen. Royce West, activist Cristina Tzintzun Ramirez and former Rep. Chris Bell.