After six days into early voting (including a weekend day), in the top 15 most populated counties, roughly 43,000 more people have cast their ballots in 2014 compared to the 2010 gubernatorial elections.

After six days of early voting; Positive numbers indicate more ballots were cast in 2014 than in 2010.
It is not a good sign for the democrats hoping to surprise the republicans with a stellar ground game. It is particularly worrisome that Harris, and El-Paso counties are lagging in early voting. At the very least, this data does not suggest that the republicans have upped their game any more for this cycle, than they have done in previous cycle. Therefore, it is possible that most of the increase in EV may come from democratic party efforts. I have summarized my additional thoughts here.