With Election Day still five days away, the number of voters taking the opportunity to cast their ballot early in Texas has already topped the Lone Star state’s entire 2014 turnout.

A further 19 U.S. states and the District of Columbia have also outperformed their 2014 early voting turnout, according to political scientist Michael P. McDonald of the University of Florida in Gainesville.

As of late Wednesday, McDonald’s United States Elections Project estimates that 25.5 million Americans had cast early votes.

“What we’re seeing is very high levels of engagement on both sides in the competitive elections for governor and Senate,” McDonald told the Washington Post.

In states with prominent Senate or gubernatorial races, McDonald’s research has discovered that both national parties seem to be succeeding in turning out voters. Among lower-key elections, however, participation seems to be slightly higher among registered Democrats, which McDonald suggests could be a consequence of voters channeling discontent with national politics into their local races.

Earlier this month, the political scientist predicted a 50-year-high in voter turnout based in part on primary participation, special election turnout, self-reported interest, and early voting at that time.

One possible reason behind the surge is that many states have made it easier for people to cast early or absentee votes in recent years, drawing in voters who would have previously cast on Election Day.

Another important factor are state-level voting rules. Vermont Secretary of State Jim Condos and former West Virginia Secretary of State Natalie Tennant wrote Wednesday in Fortune about their efforts to implement automatic voter registration, which they argue helps improve voter participation rates.