– Minnesota Democratic Sens. Amy Klobuchar and Al Franken aggressively criticized Republican colleagues Wednesday for saying they won’t hold hearings or even meet with President Obama’s nominee for the U.S. Supreme Court.

Klobuchar and Franken said the behavior amounted to an unprecedented constitutional crisis.

The two are members of the Senate Judiciary Committee — the first stop for judicial nominations from the White House. The death of Supreme Court Justice Antonin Scalia earlier in this month created a vacancy on the bench, and Obama has said he intends to fulfill his constitutional obligation to nominate a replacement, likely in coming weeks.

Iowa Republican Sen. Chuck Grassley, who is chairman of the Judiciary Committee, said all Republicans on the panel agreed that they would not grant a hearing for an Obama nominee to the Supreme Court.

Grassley said he prefers to wait until a new president is in the White House next year.

Republicans are fearful that Obama will nominate a more liberal justice, tilting the court’s balance after the unexpected death of Scalia, a reliable and outspoken conservative voice on the court. They remain hopeful that a Republican will win in November and nominate a conservative justice.

Democrats are powerless to force a vote in the Senate, so they are trying to increase political pressure in an election year.

Klobuchar on Wednesday put together a rare hearing with other Senate Democrats and constitutional scholars to talk about the rarity of the Senate refusing to hold hearings on a nominee and a Supreme Court bench with eight members, rather than nine. She also spoke on the Senate floor and urged Republican colleagues on judiciary to reconsider their positions.

“We believe this is unprecedented,” said Klobuchar, noting that since 1975 the average time between a nomination and a confirmation is about two months. When Obama announces his nominee, “it will be the constitutional duty of each one of us to consider the nominee on his or her merits — and then choose whether to vote yes or no.”

Franken, on the Senate floor, said that if Senate Majority Leader Mitch McConnell arbitrarily lops off the last year of elected officials’ terms, maybe he shouldn’t allow outgoing senators to introduce bills or vote on legislation in 2016.

“If we were truly to subscribe to the majority leader’s logic and extend it to the legislative branch, senators would become ineffective … too,” he said. “By my count, approximately 11 months remain in Barack Obama’s presidency. Eleven months is a considerable amount of time.”

Franken said that if McConnell wanted to change the rules, perhaps he should propose a constitutional amendment, which requires a two-thirds majority in both chambers of Congress and then ratification by 38 of 50 states.

“If only the American people had a voice in exactly how much time we should shave off the American president’s term,” Franken said. “This is a cynical affront to the constitutional system and it misrepresents our history.”

Republicans on Wednesday did not alter their plan.

Judiciary Committee Republicans wrote to McConnell that 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.”

The panel of constitutional experts said that holding up a nomination is unconscionable.

“If [Senate Republicans] carry through with this threat, it would be an action morally and legally on par with the Southern Manifesto,” said Geoffrey Stone, a law professor at the University of Chicago, referring to a document written by Congress in 1956 opposing racial integration of public places. Sen. Elizabeth Warren, D-Mass., a former law professor, agreed.

“Senator McConnell was right that the American people should have a voice in the selection of the next Supreme Court justice, and in fact they did when President Obama won the election in 2012 by 5 million votes,” Warren said. “In 100 years, every single pending nominee … has received a vote on the floor of the United States Senate. For the rest of this year, President Obama is still the president of the United States of America.”