Battle lines have been drawn in the fight to replace conservative US supreme court justice Antonin Scalia, threatening to turn a fraught presidential race into a pitched battle for America's highest court.
Justice Scalia died at the age of 79 from a heart attack in his sleep early on Saturday while on a hunting trip to Texas, leaving a crucial swing seat on the court in the balance.
Republicans have vowed to block attempts by Democratic president Barack Obama to fill the vacancy in an election year.
Hot topics
The array of policy issues sitting on the court’s upcoming docket means the presidential election will be transformed into a referendum on a range of hotly contest topics, from union rights to climate change, from abortion to immigration, to religious discrimination.
Promising to proceed with his nomination of a successor to Scalia, Mr Obama said there was “plenty of time” left in his presidency for the Republican-led Senate to consider a replacement.
Republicans including Senate majority leader Mitch McConnell and presidential candidates Ted Cruz and Marco Rubio have called on Mr Obama to leave the appointment to the next president.
"It is outrageous that Republicans in the Senate and on the campaign trail have already pledged to block any replacement that President Obama nominates," Democratic candidate Hillary Clinton told a crowd in Colorado.
“That is a fact, my friends, whether the Republicans like it or not,” she said. “Elections have consequences.”
Mr Cruz, a former law clerk to another conservative hero on the supreme court, said the vacancy left by Scalia would have a “profound impact” on the Republican primary. He vowed “absolutely” to block Mr Obama with a Senate filibuster.
“This is a 5-4 court – the next election needs to be a referendum on the court,” he said on a Sunday talk show. “People need to decide.”
Angry exchanges
The subject of supreme court appointments led to the angriest exchanges of Saturday night’s ninth Republican presidential debate, the nastiest of the race so far.
Personal attacks dominated the high-decibel debate in South Carolina, which holds the next primary on Saturday.
When Mr Cruz distanced himself from his support of chief justice John Roberts, Mr Trump fired off repeatedly: "Why do you lie?"
“Donald, adults learn not to interrupt each other,” Mr Cruz shot back, after claiming that the businessman would appoint liberals to the court. “Yeah, yeah, I know you’re an adult,” Trump responded.
Mr Trump jabbed former Florida governor Jeb Bush, claiming his brother, George W Bush, was partly to blame for the September 11th, 2001 attacks and made a "big fat mistake" invading Iraq in 2003.
"I could care less about the insults Donald Trump gives to me," said Mr Bush. "I am sick and tired of him going after my family."
George W Bush makes his first campaign appearance in support of his brother today at a rally in South Carolina, which has a large military presence and where the 43rd president is still hugely popular.
