Yes, thankfully I believe that Ted Cruz's 15 minutes of fame is already up. The mainstream understands that he is a far-right extremist and makes very poor decisions. He made a lot of enemies in both the Democratic and Republican parties alike. People were not generally a fan of the government shutdown which he orchestrated. He will probably always maintain his base, who seems to be fired up every time he does something bigoted or homophobic.
He is mostly know for the "filibuster" regarding the continuing resolution. He wanted to defund the ACA in return for passing the overall funding. Where he blew it was he had the floor and should have simple begun reading the text of the ACA. Many Senators might have been surprised at its content. He simply blew it.
No, Ted Cruz's political career is not dying. Politicians know what they are doing, and even though it may seem that he is going down hill, he can easily back a great political program and become more popular than he ever has, then he can keep extending his political offices.
Ted Cruz will never win a national presidential election. No matter how much he huffs, puffs, and grandstands he cannot change the fact that he is, looks, and acts Hispanic. He can't change the fact that his four letter last name sounds Hispanic. The fear laden whites in the United States are never going to let him accomplish much.
Nothing would make me happier than that scumbag disappearing permanently, but fringe voters like fringe representatives. His number of followers isn't going to go much past what it's at, but those that like him really really like him and that's a sentiment that's unlikely to change any time soon, we're stuck for a while.
Ted Cruz has proven himself to be a very controversial figure in American politics today, but its pretty hard to argue that his political career is dying. Cruz seems to appeal to a solid portion of the US population, and has done well in elections, so regardless of what people think, he's probably not going anywhere soon.