Democratic presidential candidate Sen. Bernie Sanders (I-VT) and his wife Jane Sanders wave to the crowd at the end of a campaign rally at Vic Mathias Shores Park on February 23, 2020 in Austin, Texas.

An increasingly young and diverse red state that the Democratic Party sees as a core piece of its future will get its chance Tuesday to define which white septuagenarian will represent the party against President Donald Trump.

Texas will hold its presidential primary Tuesday, joining 13 other states that will dole out more than a third of all pledged delegates in the 2020 race. The Lone Star State will allocate 228 delegates, more than any state voting this week other than California.

The huge and still growing Texas will test 78-year-old Sen. Bernie Sanders' efforts to boost turnout among young and Latino voters, core parts of a coalition he hopes will propel him to the Democratic nomination and the White House. Carried to his first primary win by overwhelming support from black voters in South Carolina, former Vice President Joe Biden, 77, hopes black voters in Texas and elsewhere Tuesday will help him keep pace with Sanders in the national delegate race.

Former New York Mayor Mike Bloomberg's appearance on ballots for the first time complicates their efforts to rack up votes in Texas. The 78-year-old billionaire, who has spent more than $500 million on his campaign across a range of states such as Texas, has made inroads with older voters of color, who have typically leaned toward supporting Biden, according to recent Texas polls.

Massachusetts Sen. Elizabeth Warren, 70, has also drawn a major chunk of support and could win delegates in Texas.

With its mammoth delegate haul, the Texas primary will play a major role in deciding who gets the nomination. It will also give a clue about whether presidential candidates can harness increased Democratic energy and a rising Latino voting bloc in a state central to the party's ambitions in the coming years.

"There is incredible progressive momentum on the ground in Texas. ... Latinos' massive growth as a voting bloc is largely driven and attributed to the youth coming of age. Young Latinos in Texas are growing in power," said Antonio Arellano, interim executive director of Jolt, an organization that aims to increase engagement and voting among young Latinos in Texas. The group has endorsed Sanders for president.

Texas typically votes Republican in presidential elections. Trump, 73, won the state by 9 percentage points in 2016. Yet Democrats have high hopes for Texas after flipping several congressional districts and coming just short of winning a U.S. Senate race in 2018. Democrats aim to defend or flip U.S. House seats around Austin, Houston and Dallas, cities with changing demographics that have made them skew more Democratic. The party also has designs on flipping the Texas state house this year.

Along with winning over disaffected independents and Republicans, mobilizing voters of color is a part of the party's strategy.

In the 2016 Texas primary, Hispanic or Latino voters made up 32% of the Democratic electorate, according to exit polls. About one-fifth, or 19%, were black.

Hillary Clinton beat Sanders by at least 40 percentage points among both groups of voters, exit surveys showed. Sanders needs those trends to change this year, and polls indicate they have.

An NBC News/Marist poll — taken before Biden's blowout South Carolina primary win and Amy Klobuchar and Pete Buttigieg's decisions to drop out of the race and endorse the former vice president — found Sanders leading among Latinos with 46% of support. Bloomberg and Biden followed at 14% and 13%, respectively.