The charts above show the early voting in Texas for the last three midterm elections. Note that this year is different -- far outpacing the early voting in 2014 or 2010. In fact, it more than doubles the early voting totals of either 2014 or 2010.
Democrats needed a huge turnout to have a chance in Texas. They got it! On election night, we'll find out if it was enough/
Note that about 40% of the registered voters have already voted.
The charts above are from the office of the Texas Secretary of State. They are totals from the 15 largest counties in the state. Those counties have 65% of the registered voters in the state.