Senate Democrats moved quickly Saturday to demand action on a Supreme Court nominee following the unexpcted death of Justice Antonin Scalia.

Senate Minority Leader Harry Reid (D-Nev.) called Scalia a “brilliant man” and “dedicated jurist” in a statement and said the work on filling his vacancy should begin immediately.

{mosads}“The President can and should send the Senate a nominee right away. With so many important issues pending before the Supreme Court, the Senate has a responsibility to fill vacancies as soon as possible,” Reid said.

“It would be unprecedented in recent history for the Supreme Court to go a year with a vacant seat. Failing to fill this vacancy would be a shameful abdication of one of the Senate’s most essential Constitutional responsibilities.”

Sen. Patrick Leahy (Vt.), the ranking Democrat on the Judiciary Committee, said the American people deserve to have a fully functioning Supreme Court.

“Although I often did not agree with his legal opinions, no one doubted his commitment or his brilliance,” Leahy said of Scalia, the longest-serving Supreme Court justice. “I hope that no one will use this sad news to suggest that the President or the Senate should not perform its constitutional duty.”

Leahy said the high court is far too important to the nation’s democratic system to be left understaffed for partisan reasons.

“It is only February,” he said. “The President and the Senate should get to work without delay to nominate, consider and confirm the next justice to serve on the Supreme Court.”

A spokesman for Sen. Mike Lee (R-Utah), a conservative who sits on the Judiciary panel, said on Twitter after the news of Scalia’s death that no nominee from President Obama should be considered.

Marco Rubio, a candidate for the White House, echoed Lee in a statement.

“The next president must nominate a justice who will continue Justice Scalia’s unwavering belief in the founding principles that we hold dear,” the Florida senator said.

“Today, our nation has suffered a deep loss,” he continued. “Justice Scalia was one of the most consequential Americans in our history and a brilliant legal mind who served with only one objective: to interpret and defend the Constitution as written.”

The conservative Judicial Crisis Network said Obama should be the last person to appoint Scalia’s successor.

“This president, who has shown such contempt for the Constitution and the laws, is the last person who should be appointing his successor,” Carrie Severino, the group’s chief counsel and policy director, said in a statement. “The American people on both sides of the aisle are disgusted with the status quo in Washington and another nomination by this President would just bring about more of the same.”

Severino said the next president should make the appointment.

“The people’s voice should be heard in November to determine who will appoint the next Supreme Court Justice,” she said.

—This story was updated at 6:34 p.m.