It’s a rise through the process of elimination. He is going to have to make it stick, as these people are the “not Trumps”, and were not fans of Cruz from the start.
You are correct that Cruz is not running on name recognition or his celebrity status, he must convert voters with his message and by his conservative principles and character. He is not in front of all the cameras, his tweets are not discussed on the news nightly, he has no TV show and the GOPe is not helping him one bit. In other words the voters have to get to know him, but then to get to know Ted Cruz is to get to know the one Constitutional conservative with a long record of integrity and courage. With Cruz, the more you look - the more you see - and the more you see the more you like - Ted Cruz for president, because liberty matters!