Maybe he’s doing the data mining/social media thing that worked well for him in 2016 and helped Trump beat Hillary although outspent 5 to 1 and with fewer workers on the ground? Cambridge Analytica worked for Cruz before they switched to working for Trump. Are you familiar with that story? TV and radio ads are a 20th Century tactic. If Cruz was spending $100 million on social media you might never hear about it.
It's clear that O'Rourke is still doing TV and radio ads (at least here in Houston), so he doesn't care if it's a 20th century tactic. He needs name recognition and he's getting it without Cruz countering. This 20th century tactic is called defining your opponent before he can define himself, and Cruz isn't doing it.
Maybe Cruz thinks he can overcome O'Rourke's media lead once he starts his own campaign. Cruz's advantage so far is that O'Rourke hasn't been attacking him, O'Rourke's been busy introducing himself to Texans.
Once they engage directly, things will be different. I just hope Cruz knows what he's doing by letting O'Rourke have the field all to himself over the summer.
-PJ