"We should not do anything before January 20, 2017," said Judiciary Committee Chairman Chuck Grassley, referring to the date when the next president will be sworn in.
The GOP's reaffirmation not to act on President Barack Obama's nominee came in the wake of Donald Trump effectively winning the Republican nomination last week. That caused some conservative activists
to press for quick confirmation of Garland. Those activists argued Trump is likely to lose the general election to Clinton, who could potentially name a more liberal justice than Garland to the bench.
A similar position has been endorsed by Sen. Jeff Flake, an Arizona Republican, who sits on the Judiciary Committee. He has argued for months -- and pushed again in a national TV interview Sunday -- that if Clinton wins the White House, Garland should be confirmed in the post-election lame duck session.
But several key GOP senators said they wouldn't change their decision and expressed optimism Trump will win the White House and a nominee more conservative than Garland will make it on the bench.
"We're not going to do that. We've said we want to wait for the election," said Sen. John Cornyn of Texas, the second-ranking Republican senator. "It looks like the race is very close and is going to have to play out over the next few months. But no, we're not going to change course."
Even Sen. Lindsey Graham, R-South Carolina, a member of the Judiciary Committee and one of Trump's fiercest critics in the Senate, said the decision should wait.
"I think the next president should pick the Supreme Court nominee," he said.
Senate Minority Leader Harry Reid, D-Nevada, blasted Republicans for trying to preserve the seat for Trump to fill.
"It appears the Republicans want their anti-woman, anti-Latino, anti-Muslim, anti-everything, anti-middle class, billionaire candidate to determine the balance of the Supreme Court for the next generation," Reid told reporters.
Earlier Tuesday, the White House delivered to Capitol Hill the formal questionnaire
court nominees must provide the Judiciary Committee, even though no hearings or votes are planned for Garland, who is now the chief judge on the U.S. Court of Appeals for the DC Circuit. The decision to send the lengthy document to the Hill was part of a months-long strategy by the White House and congressional Democrats to pressure Republicans to act.
On Wednesday, the liberal group MoveOn.Org is holding a Washington press conference with a group of Iowans who will say they are disappointed with Grassley's handling of the Garland nomination. Also, the Center for American Politics, a Democratic group, will release a report critical of Grassley's stewardship of the Judiciary Committee.
Sen. Chuck Schumer of New York, who is expected to be the next Democratic leader in the Senate, was asked if Garland is not confirmed and Clinton wins the White House, should she resubmit Garland's name in the next Congress.
"I agree with Leader Reid he'd be a great member of the Supreme Court, but I'm not going to prejudge what happens in January," Schumer said. "If we get the majority, we will spend a lot of time listening to what the new president, President Clinton, has to say. If she were to pick Garland, I think we'd all be very, very happy. If she wouldn't, obviously we'd give that nominee due consideration."