With the U.S. presidential election looming on Nov. 8, Republicans were aiming to allow the next president to fill Scalia's vacancy, hoping a Republican will be elected.
“This nomination will be determined by whoever wins the presidency in the fall,” McConnell said, adding that the overwhelming view of Senate Republicans was that “this vacancy should not be filled by this lame-duck president.”
Obama's nominee could tip the court to the left for the first time in decades. Scalia's death left the court with four liberals and four conservatives.
Not since the contentious nominations by Republican presidents of Robert Bork in 1987 and Clarence Thomas in 1991 has there been such an intense fight over a Supreme Court vacancy — and Obama has yet to announce his pick.
The White House and Senate Democrats condemned McConnell's stance. Senate Democratic Leader Harry Reid called it “obstruction on steroids,” adding: “Gone are the days of levelheadedness and compromise.”
McConnell and other congressional Republicans have sought to block numerous Obama initiatives, including his signature health care law, the Iran nuclear deal, immigration policy and efforts to battle climate change.
McConnell invoked a past statement by Obama's vice president, Joe Biden, to help justify Supreme Court inaction. McConnell noted that Biden, as Senate Judiciary Committee chairman in 1992, argued for postponing action on Supreme Court nominees during an election year.
Biden has since said he was speaking hypothetically because there was no Supreme Court vacancy at the time.
McConnell made his announcement after Chairman Chuck Grassley and the other Republican members of the Judiciary Committee sent him a letter saying the panel would not hold confirmation hearings. Grassley had previously left open the possibility of convening hearings.
Alluding to the Nov. 8 presidential election, Republican senators told McConnell in the letter they wanted “to ensure the American people are not deprived of the opportunity to engage in a full and robust debate over the type of jurist they wish to decide some of the most critical issues of our time.”
If the Senate does not consider a nominee until after a new president takes office, it would be unlikely that the Supreme Court would have its full complement of nine justices any sooner than early 2017.
That would mean the court would be shorthanded for more than a year, hampering its ability to decide cases. In cases that end in 4-4 rulings, lower-court decisions stand and no national precedent is set.
Reid said the Republican strategy was driven by the Republican Party’s right wing. “It’s what Donald Trump and Ted Cruz want,” Reid said, referring to two of the Republican presidential candidates.
But Reid said Senate Democrats would not become “the obstruct caucus” and block legislation such as appropriations bills in retaliation for the Republican inaction.
White House spokesman Josh Earnest said blocking a hearing for Obama’s nominee would be unprecedented and would “subject the Supreme Court to the kind of politics that they've been insulated from for more than two centuries.”
“Since 1875, a president's nominee has never been denied a hearing unless that president later withdrew that nomination,” Earnest said.
In remarks on the Senate floor, McConnell said, “Presidents have a right to nominate, just as the Senate has its constitutional right to provide or withhold consent. In this case, the Senate will withhold it.”
Chuck Schumer, a member of the Senate Democratic leadership, predicted that the Republican position would crumble as voters put pressure on vulnerable Republican Senate incumbents seeking re-election to consider Obama's nominee.
“It’s not just a risky strategy, it's the wrong strategy and it's going to fail,” Schumer said of the Senate Republicans.
But Sen. Orrin Hatch, a Republican Judiciary Committee member, countered, “I’m not concerned about that (public pressure). We’re standing for a principle that the next president ought to resolve this problem.”
Democrats are badly outnumbered in the 100-member Senate, falling far short of the 60 votes needed to advance controversial legislation, much less a Supreme Court nomination.
Counting the two independents who caucus with them, Democrats control 46 seats, with the remaining 54 held by Republicans.