Primaries in Texas today have drawn more than a quarter of a billion dollars in ad spending, with a highly competitive Republican Senate primary setting records and driving the staggering totals. Alone, the GOP Senate primary – a divisive clash between veteran incumbent Sen. John Cornyn and his challengers, Texas Attorney General Ken Paxton and US Rep. Wesley Hunt – accounted for about $100 million of the ad spending total, making it the most expensive Senate nominating contest on record, according to data from the ad tracking firm @AdImpact_Pol.