To be blunt, very close to too little, too late re the NRSC and Cornyn.
Strike that, DEFINITELY too little, too late, re the NRSC. If Cornyn REALLY toes the line, he MAY not lose too many of us. MAYBE. (He’a pretty decent on my hot button issue, the 2nd Amendment http://aboutpolitics.com/politicians/Texas-TX/Cornyn/Gun%20Issues but I wouldn’t trust him as far as I could throw a 10 lb weight.)
Unfortunately for Cornyn, he's got a public record that cuts against the grain of Tea Party ideals. He won't survive a challenge from the right in his next re-election campaign.
"Toeing the line" won't erase his history of RINO votes and country club elitism.