My guess is that DNC is worried about FL and rust belt states like PA OH MI so they are trying to pick off TX, based on high Hispanic population.
Pennsylvania and Michigan aren't in play. The Democrats will sink money into Florida, Ohio, and Texas because they have money to burn.
TX is a distraction. A minuscule ad buy is the tip off. If Hillary thought TX were in play, she would be down there herself campaigning. Watch where the campaigns are holding rallies and that will tell you what the target states are.