Unusually tight races were expected in Tuesday in Texas following a record-breaking three weeks of early voting, and Democrats were eyeing possible inroads to power in what has been the nation's largest Republican stronghold.

Nearly 10 million of the state’s 16.9 million registered voters had voted in Texas before Election Day, with early voting extended because of the coronavirus pandemic that has killed more than 18,000 people in the state. That surpassed the total number of votes from the 2016 general election.

The Texas House is in play for the first time in nearly two decades, while there is tighter than usual competition for multiple congressional seats in historically red districts. Democrats are even eyeing GOP Sen. John Cornyn’s seat and think they have a chance to carry the state in the presidential race.

Meanwhile, mail ballots continue to pour in from across the state after months of legal challenges from state and party officials on the absentee votes, including who was eligible and where they could be dropped off.

In Texas, voters must be 65 years or older; disabled or out of the county on Election Day and during early voting to apply for a mail ballot. Officials from the U.S. Postal Service warned the Texas Secretary of State’s office that given the state’s current ballot deadlines, they could not guarantee some ballots would make it to voters or be mailed in on time.

Polls are open from 7 a.m. to 7 p.m.

Here’s a look at some of the key races:

U.S. PRESIDENT

Following demographic shifts across the state, primarily in Texas’ most populous urban areas, the historically Republican state has seen tighter competition in the presidential race this year.

Democrats claim that economic struggles and healthcare issues highlighted by the COVID-19 pandemic will make this the year that Texas turns blue, while Republicans maintain the risk of flipping the state is overstated.

In 2016, Donald Trump took Texas by a 9 percentage point margin, with most Democratic districts located in South Texas and major cities including Austin, Houston, Dallas, El Paso and San Antonio.

CONGRESSIONAL RACES

Cornyn has not faced a challenge like Democrat MJ Hegar's since being elected in 2002. Two years ago, Beto O’Rourke's unsuccessful challenge against Republican Sen. Ted Cruz was the closest Senate race the state has seen in 40 years. O’Rourke lost by less than 3 percentage points, but flipped several longtime Republican counties including Williamson, near Austin, and Tarrant, near Fort Worth.

In the U.S. House, six Republican incumbents announced they would not seek reelection this year, and Democratic hopefuls are looking to flip those seats and more.

___

Acacia Coronado is a corps member for the Associated Press/Report for America Statehouse News Initiative. Report for America is a nonprofit national service program that places journalists in local newsrooms to report on undercovered issues.

___

Find AP’s full election coverage at APNews.com/Election2020.