I notice some Cruz opponents are trying to tar him on civil rights by equating his position with the position of Jesse Helms, who opposed the 1964 Civil Rights Act. This is classic guilt by association. A few observations:
i) There were segregationist dinosaurs like George Wallace, Strom Thurmond, Fritz Hollings, and Robert Byrd who reinvented themselves. I doubt their change of heart was sincere. I think they were ambitious politicians who adapted to a new situation. It's a pity voters didn't clean house by sweeping them out of office and making a fresh start.
ii) In all likelihood, I think Jesse Helms was of the same ilk. Given when and where he came of age, it would be surprising if he didn't support Jim Crow. So I figure he opposed the Civil Rights Act because he was a conventional racist. And I assume he softened his views later on due to political expediency.
iii) But by the same token, Cruz's social conditioning, is completely different from Helms. He's a man of a different time and place. He didn't have the same formative experiences Helms did. There's no comparison.
iv) Regarding the Civil Rights Act, there are critics like Milton Friedman who give it mixed reviews. They oppose laws that mandate discrimination as well as laws that forbid discrimination. They think Americans are entitled to equal protection under the law. But they think the private sector should be free to discriminate. For that reason, they oppose Title II of the Civil Rights Acts, which forbad discrimination in public accommodations, although they supported provisions of the same act that nullified racially discriminatory laws by state and local government.
Keep in mind that the "public accommodations" provision has become the template for LGBT rights. So there is a principled reason to be critical of Title II.
I'm not suggesting Jesse Helm had that high-minded objection. My point, though, is that there's nothing inherently racist about refusing to give a blanket endorsement to the Civil Rights Act.