Texans have already cast more ballots in the presidential election than they did during all of 2016's race — an unprecedented surge of early voting that comes as Democrat Joe Biden's campaign is making a late push to flip what has long been the country's largest Republican state.

More than 9 million ballots had been cast as of Friday in the nation's second most-populous state, exceeding its 8.9-plus million votes four years ago, according to an Associated Press tally. This year's numbers were aided by Democratic activists challenging in court for, and winning, the right to extend early voting by one week.

"Y'all have been doing your thing," Democratic vice presidential nominee Kamala Harris said during a drive-in rally in Fort Worth on Friday. "Early voting in Texas, 9 million? Now we know this is no time to let up on the pedal, though, right?"

Voters statewide don't register by party affiliation, so no one can yet know which side will benefit from the surge. Turnout has also been inflated by Texas' booming population. More than 16.9 million Texans are registered to vote in 2020, a roughly 1.8 million increase from 2016's about 15.1 million. The number of early votes accounts for only about 53% of statewide registered voters, while about 59% of registered voters cast early and Election Day ballots in 2016.

Still, the fact that the state exceeded its entire vote total for the past presidential cycle with hours still to go in an early voting period ending Friday evening — and before millions are likely to cast Election Day ballots — hints at a potential electoral sea change.

For Democrats, anything different is likely positive. The party hasn't won a state office in Texas since 1994 — the nation's longest political losing streak — nor seen one of its presidential nominees carry the state since 1976. The party now believes it has a chance to seize control of the state House and flip as many as six congressional seats and a Senate seat.

President Donald Trump carried Texas against Hillary Clinton in 2016 by 9 points, but that was the smallest margin of a GOP presidential victory since 1996.

Texas has the highest share of its registered voters who are either new or infrequent voters of any battleground state, according to an Associated Press analysis. Roughly half of its voters have either never cast a ballot or done so in half or fewer of the elections for which they were eligible.

So far, 36% of Texas' vote comes from this group of irregular voters. That could bode well for keeping Texas Republican since that's precisely the cohort Trump's campaign is trying to appeal to as it looks to expand his conservative base.

Meanwhile, because Texas is one of the few states that maintained its already-strict rules preventing most residents from using mail ballots during the pandemic, some of the lines at in-person early voting locations may reflect it being the only way most voters can cast a ballot before Election Day — further potentially inflating the totals.

Democrats nonetheless point hopefully to areas like Harris County, the state's largest and home to Houston, where they swept every major election in 2018, to argue that the state is fast becoming bluer. About 1.3 million Harris County voters had cast early ballots so far compared with less than 980,000 in 2016, and the percentage of registered voters countywide voting early had reached about 58% so far, compared with 54% in total early voting four years ago.

Biden's campaign has for months insisted that Texas, with its 38 electoral votes, is among the traditionally conservative states it is looking to flip — though it has long been more bullish on Arizona. After Fort Worth, Harris visited the U.S.-Mexico border town of McAllen, and Houston. The news may not be all positive for Harris' party, however.

Early voter turnout increases in Hidalgo County, which includes McAllen, hasn't matched other places, like the suburbs of Dallas and Austin. It is part of the Rio Grande Valley.

The area has been among the hardest-hit areas in the nation by the coronavirus and has seen new cases soar in recent weeks as they have in many parts of the country.

"This part of Texas has borne witness to the cruelty of the Trump administration and the incompetence of his leadership," said Beto O'Rourke, a former Texas congressman and Democratic presidential candidate who came within 3 percentage points of upsetting GOP Sen. Ted Cruz in 2018.