The 2020 presidential election is projected to have record voter turnout, and the once-safe Republican state of Texas is shaping up to be a competitive battleground.

Over the course of just a few weeks in July, four incumbent Republican congressmen who represent suburban and majority non-white districts all decided to call it quits and not run for re-election in 2020.

White, college-educated voters in Texas' growing suburbs who dislike President Donald Trump are fleeing the Republican party, and voting out their representatives.

Meanwhile, Texas is gaining new Latino residents at a rapid pace — and neither party has a clear monopoly on Latino voters in Texas.

"The narrative that Hispanics will turn Texas blue may eventually happen, but that's not moving as fast as the fact that college-educated whites are telling us they don't like Donald Trump," one GOP strategist told INSIDER.

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The 2020 presidential election is projected to have record voter turnout, and the long-time Republican stronghold of Texas is shaping up to be a battleground state.

Republicans' margins of victory in the state have been narrowing over the course of the last few election cycles, especially in Texas' suburban areas.

And over the course of just a few weeks in July, four incumbent Republican congressmen all decided to call it quits and not run for re-election in 2020 in what some commentators have termed a "Texodus."

Three of the retiring congressmen, Rep. Pete Olson of Texas' 22nd district in the Houston suburbs, Rep. Will Hurd of the 23rd district along the border, and Rep. Kenny Marchant of the 24th district in the Dallas-Fort Worth metro area all represent majority-nonwhite, suburban districts that have been trending towards Democrats in recent election cycles.

Not only do retirements automatically make many seats more competitive, but Texas is currently experiencing two trends that are favorable to Democrats: increasing urbanization, and big demographic shifts.

Texas' Latino population is growing fast — but it won't hand Democrats control of the state overnight

The Texas Tribune recently reported that Hispanics are expected to become the largest demographic group in the state by 2022, with Texas gaining nearly nine times as many Hispanic residents as white residents.

As the Tribune noted, almost half of Texas' Hispanic population is concentrated in the state's five largest counties, and Hispanic voters in Texas "are registering and voting at significantly higher rates than their population is growing," according to a Houston Chronicle analysis.

The current rate of population growth among non-white Texas residents is a positive development for Democrats, but they can't take voters of color for granted.

Despite Latino turnout doubling in Texas between the 2014 and 2018 midterms, according to one analysis, Democrats do not hold a monopoly on Hispanic and Latino voters.

As the Pew Research Center noted, 65% of Hispanics voted for Rep. Beto O'Rourke while 35% backed Sen. Ted Cruz in their high-profile Senate race in 2018. And a slim majority of Hispanic voters — 53% — backed Democrat Lupe Valdez over incumbent Gov. Greg Abbott, who received 42% of the Latino vote.

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Washington Post data columnist David Byler argued that while a blue Texas is a "Democratic dream" for now, the GOP could be putting itself at a disadvantage by embracing the Trump's administration's harsh and controversial immigration policies, leaving lots of Latino and Hispanic voters on the table instead of courting them.

Ford O'Connell, a veteran GOP campaign strategist and adjunct professor at George Washington University's Graduate School of Political Management, told INSIDER that while the increase in the state's Latino population is an important demographic change, Texas' current leftward shift can be attributed more to white suburbanites breaking with President Donald Trump's Republican party.

"The narrative that Hispanics will turn Texas blue may eventually happen, but that's not moving as fast as the fact that college-educated whites are telling us they don't like Donald Trump," O'Connell said.

The Obama-Trump voters who helped Republicans carry competitive states in the Upper Midwest have been the subject of a significant amount of media scrutiny since the 2016 election.

But suburban voters who flipped from Mitt Romney in 2012 to Hillary Clinton in 2016 in states like Texas have received far less attention, despite the critical role they could play in turning Texas, a GOP stronghold for four decades, into a swing state.

Beto O'Rourke has ruled out running for Senate a second time in 2020. Reuters

Texas voters are punishing Trump-aligned Republicans

The prospects of past Republican presidential nominees, including Mitt Romney and John McCain, and the GOP more broadly have hinged on the support of suburban, college-educated voters in the state who are concentrated around urban centers like Houston and the Dallas-Fort Worth area and in many cases, are fleeing the GOP altogether.

"Texas' cities are getting bigger in areas like Houston, Dallas, and Austin, it's the white folks in Texas whose votes are changing," O'Connell said. "You have more college-educated voters in those cities because they also have booming economies, and it's these college-educated whites who don't like Donald Trump."

Trump won Texas in 2016 with 52% of the vote compared to Romney's 57% in 2012. And in many of the suburban congressional districts that Romney easily carried in 2012, Trump either lost to Clinton or barely cleared over 50% of the vote. Since taking office, Trump's approval rating in the state has dropped by 14%, according to Morning Consult.

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Romney carried Texas' 7th and 32nd congressional district in the Houston and Dallas suburbs, respectively, by comfortable double-digit margins in 2012, but Clinton narrowly won both in 2016, according to data compiled by the Daily Kos. Democrats ended up flipping both seats in the 2018 midterms.

Romney similarly carried the soon-to-be-open seats in Texas 22nd and 24th districts by huge margins of 26% and 22% respectively, and narrowly held the 23rd by a little over two percentage points.

But in 2016, Clinton carried the 23rd by over three percentage points with Trump holding the 22nd and 24th districts by single-digit margins, a far departure from Romney and McCain's previous blowout victories in those areas. And in 2018, Hurd won his re-election bid by fewer than 1,000 votes.

Not only did Democrats flip two suburban House seats in 2018, but former Rep. Beto O'Rourke came within just three percentage points of ousting Sen. Ted Cruz, the best statewide performance for a Texas Democrat in decades.

"Texans are not particularly big fans of Donald Trump in the way that they are of other Republicans," O'Connell said, noting that many Texas voters were sending Cruz "a message" about their disapproval to Trump by giving Cruz — who they view to be aligned with Trump — a slim victory over O'Rourke while re-electing Abbott by a much more comfortable margin.

—J. Miles Coleman (@JMilesColeman) February 7, 2019

"The problem there comes down to a very simple thing and that is, is that the entire ticket is tied to Trump," O'Connell said of Texas Republicans. "So you either have to carve out your own brand or you have to rub a rabbit's foot and hope for the best."

Benjamin Ray, a Democratic strategist and communications specialist at the pro-choice political action committee EMILY's List, told INSIDER that long-time Republican members of Congress retiring in formerly safe districts presents a "great opportunity" for Democrats and a glaring warning sign for the GOP.

Read more: Rep. Will Hurd is the 9th GOP house member to announce he's retiring this year, and it may jeopardize the GOP's chances of a House takeover in 2020

Ray further pointed out that many of the districts in the Houston, Dallas, and Austin suburbs were specifically gerrymandered to optimize the chances of a Republican victory, making it all the more concerning that Republicans' margins of victory in those areas are getting slimmer over time.

"They drew these maps for one particular version of the Republican party to do well in, and the voters that they're counting on don't think that their Republican representatives are speaking for them anymore," Ray added.

He said of the retiring congressmen, "these folks have been in politics for a while, they can tell which way the wind is blowing, and they're heading for the exits. That doesn't just happen by accident."

Ultimately, it'll come down to who shows up

As many Democratic campaign strategists and political scientists frequently say, Texas is a less of a Republican state than it is a non-voting state.

In 2018, Texas improved on their 2014 midterm turnout rate by 18%, with 46.3% of registered voters coming out to vote, but still ranked among the lowest states in voter turnout in the 2018 elections, according to the Dallas Morning News.

And in 2020, Democrats will be aiming not just to flip several House seats, but to defeat GOP Sen. John Cornyn — all of which will be reliant on high turnout at the top of the ticket.

Ray told INSIDER that the Democratic strategy to win back House seats will necessarily involve both flipping Trump-skeptical suburban voters and increasing turnout among nonvoters — the latter of which was a major component of O'Rourke's 2018 campaign strategy.

"There's nothing like the presidential election to get voters to show up, and I think that all signs point towards a very high turnout in 2020," Ray said. "In a state like Texas, I have to think that Democratic campaigns regard that as good news."

Correction: An earlier version of this article incorrectly stated that 53% of Hispanic voters backed Gov. Greg Abbott and 42% voted for his Democratic challenger Lupe Valdez. This article has been updated with the correct data to reflect that 53% of Hispanics backed Valdez and 42% voted for Abbott.