And now, with the death of Justice Antonin Scalia, Cruz is further using the Supreme Court as way to differentiate himself from other candidates and warn of the perils that will come if someone other than him is able to appoint justices. Cruz warning of a country with "unlimited abortion on demand" if the next Supreme Court justice is a liberal.
"I will have no more solemn responsibility than nominating a justice to replace Antonin Scalia on the Supreme Court," Cruz said, warning that "two branches of government are at stake."
The senator, a clerk for former chief justice William H. Rehnquist, recalled his 20-year relationship with Scalia to an audience here Monday.
Scalia was a "lion of the law, a lion of the Constitution," Cruz said. "He was brilliant, he was incredibly principled, he was a voluble Italian."
For as much as Cruz now attacks the court, it helped shape him. Cruz tailored his entire experience at Harvard Law School toward securing a clerkship, figuring out the right balance of recommendation letters and overstating his ability to play tennis to Rehnquist.
"In high school, I decided that being a law clerk at the Supreme Court, working alongside nine of the most revered judges in the land, would be one of the coolest jobs in the world,” Cruz wrote in his book, "A Time for Truth."
As a lawyer, Cruz argued before the body nine times. He said he modeled his arguments after those of the current chief justice, John G. Roberts Jr. Cruz had long admired Roberts and helped recruit him to work on the 2000 recount for George W. Bush; he also wrote a piece in 2005 praising Roberts as a "mainstream judge." Times have changed: Cruz now bashes Roberts for authoring the court's majority opinion upholding key provisions of the Affordable Care Act last year.
Cruz has said the court under Roberts is acting as a "super-legislature" and that "five unelected lawyers" are dictating policy. It is a court that, Cruz said, is "extreme" and "radical" and disregarding the law.
Cruz started attacking the court after two decisions in June: upholding portions of the Affordable Care Act and legalizing same-sex marriage nationwide. Cruz called for a constitutional amendment subjecting justices to periodic judicial retention elections after the June decisions.
The court, Cruz said in an interview in July, "is an institution that I have spent the majority of my adult life working in and around." He often cites cases he was involved with at the court -- specifically District of Columbia v. Heller, where the court, in a majority opinion written by Scalia, struck down Washington's law banning handgun possession and forbidding their registration. Cruz, as solicitor general of Texas, authored a brief to which 30 other states signed on.
Cruz often talks about religious liberty cases he was involved in before the court: one where he defended the constitutionality of a Ten Commandments monument on the Texas capitol grounds and another he was involved in that involved a cross at a veterans memorial.
He now warns of a court that would strip "the crosses and stars of David from the tombstones of fallen soldiers," as he said in Greenville, S.C., on Friday. He said Monday that if the court gets one more liberal justice, "our religious liberty will be stripped away."
And he slammed Donald Trump for once saying he thought his sister, a federal appeals court judge, would make a good Supreme Court justice.
“Now it’s good to stand with your sister, but Donald’s sister was a Bill Clinton-appointed federal appellate judge who is a radical pro-abortion extremist,”Cruz told reporters in Aiken.
In July 2000, Trump’s sister, Maryanne Trump Barry, wrote the majority opinion on a panel that found New Jersey’s ban on late-term abortions unconstitutional. It said the law banning the procedure was “constitutionally vague” and “unduly burdened a woman’s constitutional right to obtain an abortion.”
Cruz has vowed to filibuster President Obama's eventual nominee to the court -- the crowd here booed when he reminded it that Obama plans to make an appointment. Cruz said that he would not only apply a legal test to anyone he would nominate.
"The test all of us should apply to Supreme Court justices or presidential candidates is the biblical test, you shall know them by their fruits," he said.
And expect this to be one of Cruz's biggest issues this election season.
"I intend to make 2016 a referendum on the Supreme Court," he said.