Article saying it’s CRuz campaign manager’s company, Remington Research, doing the push poll calls.
From the WaPo article.
Title - ‘You didn’t hear this from me, but...’: Why South Carolina primary politics are so dirty
“Barrett said she found the call - which continued to say negative things about Rubio before taking shots at Donald Trump for being a supporter of eminent domain - to be “negative” and “unfair,” but she couldn’t figure out right away who it was from. The voice said the poll was conducted by some place called Remington Research.
She told her Rubio-supporting friend about the call; her friend told the campaign. They said they knew exactly what Remington Research was: a consulting firm started by Sen. Ted Cruz’s campaign manager, Jeff Roe. “ -snip-