And unlike other major reforms that have been rushed through Congress, Rubio and others have publicly pleaded for the immigration proposal to be slow-walked – to receive the appropriate vetting and let all lawmakers read the bill and present their proposals.
"If you have a problem with any portion of the Senate legislation, come forward with what your solution is to fix it because what we have right now is de facto amnesty," says Jennifer Korn, executive director of the Hispanic Leadership Network, a conservative pro-reform group. "Being constructive in the debate is going to be looked upon more heavily than just the dissenter saying 'No, we can't do this.'"
But Cruz continues to blaze his own conservative path and has not offered an alternative proposal that copes with the 11 million living here illegally, according to his office.
"He is opposed to a path to citizenship that rewards those who have broken our laws and flies in the face of those who went through the legal channels to come here," Frazier says. "There's no good reason to push everything through at once and risk killing the entire piece of legislation."
Korn acknowledged the political calculations before Cruz, but says the growing number of Republicans coming out in favor of reform – such as Sen. Rand Paul, R-Ky., and Rep. Paul Ryan, R-Wis., - are forming a critical mass that could render knee-jerk opposition moot. Both Paul and Ryan are considered top 2016 GOP presidential prospects as well.
"If you don't like everything that's in it, fix what you don't like; don't just be against it because – that's just silly," she says.