Editor's note: This story has been updated throughout.

PIERSON, Iowa — As he redoubles his anti-Washington crusade on the presidential campaign trail, Ted Cruz is receiving an assist from an unlikely source: the high court he used to argue before.

With its back-to-back rulings this week upholding a key part of the Affordable Care Act and legalizing gay marriage in all 50 states, the United States Supreme Court delivered a one-two punch of conservative defeats with deep implications for a GOP intent on taking the White House back in 2016.

But the decisions also gave Cruz, the former solicitor general of Texas, fresh ammo for two of his favorite targets: judicial activism and weak-kneed Republicans. The renewed offensive came full circle on Saturday, when he delivered a blistering attack on the Supreme Court, accusing it of being a part of a bipartisan "Washington cartel" hellbent on accumulating power.

"This week's assault was but the latest in a long line of judicial assaults on our Constitution and the commonsense values, the Judeo-Christian values, that have made America great," said Cruz, who later declared that the court's "hubris and thirst for power have reached unprecedented levels."

In content and style, the hourlong speech at Drake University in Des Moines, titled "Believe Again," was Cruz's most notable as a presidential candidate, and his campaign had billed it as "landmark." But it also doubled as a platform to consummate his renewed commitment to Iowa with an eye on its evangelical vote.

Cruz did not waste time taking aim at either the court or fellow Republicans as he stumped a day earlier across northwestern Iowa, a conservative stronghold where locals solemnly nodded along as the senator declared that the "last 24 hours at the Supreme Court were among the darkest in the history of our nation."

"More than a few Republicans issued slightly condemning statements, but were quietly thrilled, relieved, celebrating and popping champagne because they're afraid to defend marriage," Cruz said during a stop in Pierson. "They don't want to have to talk about it anymore."

"Several 2016 candidates today put out statements saying, 'The matter is decided. It's the law of the land. It's time to move on,'" Cruz continued. "We are in a very strange place when Republican presidential candidates are echoing Barack Obama's talking points."

The broadside, repeated several times Friday by Cruz in reference to the two recent rulings, implied a contrast with more moderate Republicans such as former Florida Gov. Jeb Bush, who reacted to the decisions with a less heavy dose of defiance.

U.S. Rep. Steve King, a firebrand conservative who represents northwest Iowa, agreed with Cruz that now is not the time for the GOP to wind down its battles against the Affordable Care Act and gay marriage.

"We can't just sack up our bats and go home because the Supreme Court overreached," King told reporters while waiting for Cruz in Pierson. "We're going to have to crack them in the knuckles instead."

Cruz was already doing that earlier Friday during a stop in Sheldon, Iowa, declaring that the court has "thrown its very legitimacy into question" with the two recent rulings. Later in the day, he wrote an op-ed proposing a constitutional amendment that would implement eight-year retention elections for Supreme Court justices.

The idea earned raucous applause Saturday as Cruz tied it to a triumph still fresh in the memories of Iowa's most ardent social conservatives: the successful effort in 2010 to oust three state Supreme Court justices after the court legalized gay marriage in the state.

"In 2010, the people of Iowa stood up to a Supreme Court that issued the same lie that the Supreme Court issued yesterday," Cruz said. "The people of Iowa threw off the judicial tyrants. We've done it before, and we will do it again."

On Friday, Cruz had particularly strong words for Chief Justice John Roberts, a decades-long acquaintance whom he once enthusiastically backed. But now, like many conservatives, Cruz faults Roberts for handing the Obama administration two high-profile wins on the Affordable Care Act.

"I respect and admire him greatly, but his decision [on Thursday], his decision a couple of years ago, violated his oath of office, and it violated the promise he made to the Senate and the American people to faithfully apply the law," Cruz told reporters in between visiting businesses in Orange City, Iowa. "He’s a talented enough lawyer and jurist — he was often referred to as the finest Supreme Court advocate of his generation — but he knows full well that he’s changing law and not following it, and that is very disappointing, particularly from someone I have known and respected for a long time.”

To many court observers on the right, the two rulings have underscored the need for a president who will appoint truly conservative judges.

"Everything else a president does evaporates after he leaves office," said Carrie Severino, chief counsel and policy director at the Judicial Crisis Network.

Cruz stressed that point in Sheldon but did not let it go unmentioned that he has already worked to get out in front of the high court, specifically on gay marriage. Earlier this year, he introduced a constitutional amendment that would let states define marriage as between a man and a woman. On Friday, he acknowledged that amending the Constitution would be an uphill battle in Congress, likely leaving it up to states to take matters into their own hands on either the Affordable Care Act or gay marriage.

"If Congress will not respond, I think you will see more and more movement towards an Article Five convention of the states to adopt those amendments," Cruz said in Pierson, referring to the part of the Constitution that allows at least two-thirds of state legislatures to call a national convention to amend the document in the absence of congressional supermajorities.

The prospect of an Article Five convention was particularly well-received in Pierson, where he drew more than 100 people to a baseball diamond and offered his fieriest remarks of the day on gay marriage. In both Sheldon and Pierson, he ended his speech with a reminder that his top adviser in Iowa, Bryan English, worked on the campaign to remove the Iowa Supreme Court justices.

The national news, though, was clearly weighing on the minds of the Iowans that Cruz encountered Friday. In one-on-one conversations, some brought it up before he could even mention it, including Kathy Mulder, the owner of a bakery Cruz visited in Orange City.

The justices, she said after chatting with Cruz, "don't have the moral compass that I think a judge should have. They all have their own agendas."