The 2018 primary elections kick off this week, and Democrats are already seeing reasons to be excited deep in the red, beating heart of Texas.

The Lone Star State holds the nation's first primary on Tuesday, but the initial eight days of early voting through last Tuesday already showed Democrats reaching record levels in a midterm year. To that point, they'd surpassed GOP voter turnout and their own party's numbers during the same period in 2016, a presidential election year where voting numbers are typically much higher.

The rising Democratic enthusiasm mirrors what the party has already seen across the country in the nearly year and a half since President Trump was elected — more than three dozen state legislature seats changing hands, important wins in Virginia and New Jersey last year and mobilization through rallies and protests.

Texas's primary brings the first actual voting in the 2018 midterm cycle, giving both parties a chance for a more concrete measure ahead of November's elections. Early signs of such a swell in a bulwark red state could be an even more ominous sign for Republicans nationally this fall if it's borne out by Tuesday's results.

"Texas is the nation's bellwether right now," said Tariq Thowfeek, the communications director for the Texas Democratic Party. "It's a good gauge of the incredible progressive energy we have across the country in a state that is ranked at the bottom of the barrel in voter turnout."

After the last day of early voting on Friday, the Cook Political Report's David Wasserman found that in the top 15 counties in the state, the Democratic early vote had spiked 105 percent over 2014 numbers. On the Republican side, there had been only a 15 percent uptick.

A surge in Democrats on the ballot

It's not just an uptick in Democratic voters happening in Texas, but an increase in candidates putting their names on the ballot, too. Democrats are fielding a modern-day record number of candidates across the state. There are 111 U.S. House candidates running for the minority party, and they are spread across all 36 Texas congressional districts — the first time that's happened in 25 years, and a departure from two years ago when Democrats didn't run candidates in eight seats.

On a state legislative level, Democrats have candidates in 132 of the 150 state House districts and in 14 of the 15 state Senate districts up for election this year. That includes four Senate districts where Democrats didn't field candidates in 2014 or 2012, and 20 new House districts where they didn't have candidates in either 2016, 2014 or 2012.

Cal Jillson, a political science professor at Southern Methodist University, said that the Democratic surge is even more impressive given that it's usually GOP voters, not Democrats, who have been reliable in non-presidential years.

"It's one word — enthusiasm. In a midterm election like this, what you normally expect to see is the Republicans' primary turnout might be twice what the Democratic turnout is, so to have the Democrats even with, and even slightly ahead, of Republicans in this midterm election is really extraordinary," Jillson said.

Key suburban swing districts are likely to determine control of the House in 2018. There are several GOP-held districts like that which could be at play in Texas, such as Rep. Pete Sessions's suburban Dallas seat and Rep. John Culberson's suburban Houston district, which, along with Rep. Will Hurd's expansive border district that runs from San Antonio to El Paso, all voted for Hillary Clinton over Trump in 2016.

"Going into this year, there was an expectation following the Women's March, in the wake of the elections in New Jersey and Virginia and all these special elections that something similar was likely to happen in the first-in-the-nation Texas primary, and I think it has," SMU's Jillson said. "It signals a Democratic electorate that is motivated to make a statement against Donald Trump, and that motivation is nowhere more powerful than in female voters."

There's been a downside to the Democrats' surge of candidates in some places, however. In the primary to face Culberson, the Democratic Congressional Campaign Committee recently lobbed attacks against one candidate they didn't feel would be a strong challenger given past derisive comments about places in the state. That move prompted a backlash from some progressive groups and criticism from the head of the Democratic National Committee.

Matt Angle, a longtime Texas Democratic strategist and director of the Lone Star Project, said the sheer number of candidates was still a positive thing for Democrats in a state where they've had trouble recruiting in the past, and noted that other primaries have been more civil. Those are encouraging signs, he said, for the way the state is trending politically.

"Make no mistake — it's a tough lift in Texas. It's a state still that is a right of center state, but I'm very encouraged," Angle said. "The excitement being generated now among candidates will not only build, it will consolidate."

Backlash to Trump

President Trump under-performed past GOP presidential nominees in the state, carrying it in 2016 by only single digits, and a Gallup poll released at the end of January showed that the president's approval rating in Texas had dropped below 40 percent.

While Trump's approval among Republican base voters remains strong, that dissatisfaction with the president is certainly driving Democratic turnout and convincing more disaffected voters to turn blue, Angle argued. For example, that has helped Democratic Rep. Beto O'Rourke in his upstart campaign to unseat Republican Sen. Ted Cruz. While O'Rourke still remains an underdog, he's been drawing large crowds and has even outraised Cruz recently with the help of small-dollar donors.

"In Texas, I think what you do have a chance to do is build a really strong coalition of Democrats, independents and fair-minded Republicans who are disillusioned with the type of leadership they're getting," Angle said.

Texas GOP strategist Derek Ryan pointed out that Democrats do have some major statewide primaries, such as the gubernatorial race, that could be driving some turnout, but admitted that Democrats have done a good job of recruiting candidates across the board, thus making those competitive races more appealing to some voters.

Ryan also acknowledged that the rise in Democratic enthusiasm is worrisome for Republicans — especially because Democrats have gotten many low propensity voters to the polls. He's been diving into the early voting data, and his analysis found that many of those primary voters are ones that voted in 2016 — but haven't had a proclivity to vote yet in a midterm year when turnout typically drops off. And nearly a quarter of Democrats who cast early ballots were new voters who just registered in the past two years.

On the GOP side, Ryan found that first-time primary voters only made up about 10 percent of the early vote share, which is a dip from the 2014 midterm primaries. However, on the Democratic side, first time primary voters comprise over 22 percent of the early vote — way up from the 14 percent four years ago.

"While I don't think that Texas is going to turn blue this cycle, I do think with these turnout numbers, it could have a significant impact in some races, and some leaning Republican races in November," Ryan said.

Matt Mackowiak, another Republican strategist in the state and chairman of the Travis County GOP, argued that the true test of Democratic enthusiasm will be on Tuesday night. He pointed out that early voting numbers also looked strong for Clinton back in 2016, but that was her high watermark and Election Day voting couldn't match Republican totals.

"For Republicans, if this is evidence of a significant enthusiasm gap, then that would be something to worry about," Mackowiak said. "I'm not sure that it is yet, and just because you have stronger turnout in the primary doesn't mean it translates into Election Day vote in November."

But he admitted that the early numbers should give Republicans some pause and they certainly don't hold any good news if the trend continues on Tuesday.

Copyright 2018 NPR. To see more, visit http://www.npr.org/.