The Nevada Democrat set a vote for next week on the stalled nominees, including the U.S. labor secretary, the Environmental Protection Agency administrator, the Consumer Financial Protection Bureau director and three members of the National Labor Relations Board.
Senate Minority Leader Mitch McConnell, R-Ky., said if Reid carries out his threat and changes the filibuster rules, he would "be remembered as the worst leader of the Senate ever."
McConnell said Reid's threat to disregard rules and precedent and end filibusters by simple majority votes, rather than supermajorities of 60 votes for the confirmation of Cabinet-level and other executive-branch presidential appointees, would damage the Senate irreversibly.
"No majority leader wants written on his tombstone that he presided over the end of the Senate," he said.
"These are dark days in the history of the Senate," he said.
Senators from both parties planned to meet Monday evening in an attempt to avert the rule standoff.
Reid said he simply exhausted all other options after Senate Republicans refused to stop abusing the Senate rules to keep President Obama from getting his choices to lead federal agencies.
He also cited a GOP's promise to filibuster any other nominee for the Consumer Financial Protection Bureau unless Democrats agree to weaken the agency.
"It is a disturbing trend when Republicans are willing to block executive branch nominees even if they have no objection about the qualification of the nominee," Reid said.
GOP lawmakers are blocking Obama nominees not because the men and women are unqualified but because the lawmakers are hostile toward the agencies the nominees are named to lead.
"The place doesn't work," Reid told reporters. "The American people know the dysfunction we have here. And all we're asking is let the president have his team."
While McConnell called the standoff an "absolutely phony, manufactured crisis," Reid said: "Please. Please. If anyone thinks since the first of the year that the norms and traditions of the Senate have been followed by the Republican leader, they're living in Gagaland," The New York Times reported.
McConnell pointed to all the Cabinet nominees the Senate has approved. He didn't mention the recent GOP filibusters Reid cited, including the first-ever attempt to filibuster a defense secretary nominee.
A filibuster is an obstructive tactic to prevent a measure from being brought to a vote. Filibustering senators are allowed to speak for as long as they wish on any topic they choose.
The filibuster can be stopped when 60 senators vote to end debate and bring the filibustered matter to a vote. The Reid move would change the number 51.
A 60-vote threshold to end filibusters would remain for judicial nominees and legislation.
The "nuclear option" -- a term coined by Sen. Trent Lott, R-Miss., in 2003 -- would not only change the voting requirement for a filibuster override. The very act would also disregard the voting requirement to change a Senate rule.
Changing Senate rules normally requires 67 votes. But the nuclear option would also make that vote a simple majority.
Democrats control the Senate, 54-46.
Lott said he called the option "nuclear" because he saw it like a nuclear strike that could provoke comparable retaliation by the minority party. And the minority eventually becomes the majority.
Sen. Roger Wicker, R-Miss., got Republicans and Democrats to agree to a "summit" meeting at 6 p.m. Monday to discuss the rules issue.
The summit, which Reid supports, is to be held in the Old Senate Chamber, Wicker said.
The red-velvet-draped semicircular two-story room in the Capitol, with a half-domed ceiling and mahogany furniture, is where the Senate met from 1810 to 1859. It's now preserved essentially as a museum.
Wicker's recommendation of that room, from the early days of the federal republic, underscored the gravity with which senators consider any change of their governing rules, the Times said.
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