By Julie Chang and London Gibson – American-Statesman Staff

In the state’s 15 counties with the most registered voters, 51 percent more Democrats voted Tuesday, the first day of early voting for the party’s March 6 primary, than voted on the first day of early of voting for the 2014 Democratic primary.

Meanwhile, the number of Republican primary voters on Tuesday increased by just 16 percent in those 15 counties, compared with the first day of early voting in the 2014 GOP primary, a comparable, midterm election with most statewide offices on the ballot.

Dissatisfaction with the leadership of President Donald Trump and the Republican-held Congress and more contested Democratic races across the state might help explain the jump in Democratic turnout on the opening day of the 12-day early voting period, according to political analysts.

“We have a segment of Democratic voters who are chomping at their bit to go out to demonstrate their opposition to President Trump, and this is a concrete way to do so, which is participating in the Democratic primary,” Rice University political scientist Mark Jones said.

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Jones added that more Democrats will likely vote in the general election in November than voted four years earlier, but it’s too early to say by how much or if they’ll swing major elections.

If mail-in ballots, which voters have been returning since January, are included in Tuesday’s primary turnout, the number of Republican voters in the 15 counties still outnumber Democrats — 47,000 versus 44,000.

Travis County Republican Party Chairman Matt Mackowiak said it’s too early to call Tuesday’s turnout a boon for Democrats.

“I think there’s a risk in analyzing one day. It doesn’t really matter which day you’re voting on,” he said. “Sometimes what you have is you have one party cannibalize its election vote with early voter turnout.”

Across Central Texas, voter trends were similar when comparing turnout on Tuesday with the first day of early voting in 2014:

• In Travis County, the number of Democratic voters more than doubled to 3,300 while the number of Republican voters grew by about 9 percent to 1,100.

• In Williamson County, the number of Democratic voters quadrupled to 825 while the number of Republican voters doubled to 1,100.

• In Hays County, the number of Democratic voters doubled to 450 while the number of Republican voters increased by 68 percent to 480.

• In Bastrop County, the number of Democratic voters increased by 76 percent to 380 while the number of Republican voters increased by 67 percent to 140.

The biggest growth among the state’s largest counties was in El Paso County with 12 times as many Democratic voters on Tuesday than the first day of early voting in 2014 — 2,800 compared with 235. U.S. Rep. Beto O’Rourke, D-El Paso, has garnered much fanfare among liberals statewide in his bid to unseat U.S. Sen. Ted Cruz, R-Texas.

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Officials with the Texas Democratic Party said the early voter turnout so far is symptomatic of the high number of Democrats candidates — 323 in congressional and state legislative races. There are 311 Republicans running for congressional and state legislative races.

“Texas Democrats are more competitive than ever before. We have a historic number of Democratic candidates in virtually every level of office,” said Texas Democratic Party Chairman Gilberto Hinojosa.

With the voter fervor, Democrats are targeting Republican-held congressional seats in the Houston area, the Dallas area, West Texas and two in Central Texas: the 21st Congressional District, which is held by retiring U.S. Rep. Lamar Smith, R-San Antonio, and the 31st Congressional District, held by U.S. Rep. John Carter, R-Round Rock.

Derek Ryan, an Austin-based political consultant and former research director of the Texas Republican Party, said Tuesday’s result is no litmus test for the ultimate primary turnout. He said Tuesday’s rainy weather in much of the state might have played a factor in the Republican turnout.

Daron Shaw, co-director of the Texas Politics Project at the University of Texas, said the first-day early voting results are sometimes overinterpreted.

“I wouldn’t read too much into first day early voting numbers,” Shaw said.

Texas Democrats optimistic after early voter turnout numbers more than double in some counties this week AP Photo/Sue Ogrocki, File