worth, the pumps ran dry today. and now the growing calls to investigate after authorities said that power gid was clo er to full collapse. the state utility had been advised to winterize their grid after that similar emergency a decade ago -- what was done. and amid all of this, the outrage tonight after these images went viral. texas senator ted cruz flying to cancun with his family on vacation when millions in his home state were without power. how he's now explaining himself tonight. but we're going to begin with the emergency and the millions still in need of help. abc's marcus moore leading us off from dallas again tonight. >> reporter: tonight, power finally coming back to hard-hit texas, albeit slowly. but some 13 million people in the state still must boil water to drink. and tonight, serious questions about why problems with their electrical grid weren't fixed after a similar situation a decade ago. officials revealing today that on sunday, demand was so high and conditions so cold, the entire grid was moments away from catastrophic failure. >> it was seconds and minutes,