When Sen. Jeff Merkley arrived in Congress in 2009, one of his first crusades was to curtail the power of the filibuster, which he thought was halting much of Democrats’ wish list under President Obama.
After four years of working over his party leaders, Mr. Merkley got his way. Sen. Harry Reid, the Democratic floor leader, triggered the “nuclear option,” a shortcut to change the rules and reduce the power of the filibuster for all nominees save for the Supreme Court. At the time, Mr. Merkley called it a victory for democracy.
Fast-forward to this year and Mr. Merkley is again on a crusade — this time to save the filibuster from Republicans, who are looking to finish what Democrats started and eviscerate the 60-vote blockade of Supreme Court nominees.
The Oregon Democrat is by no means the only member of the Senate to change his position based on whether he was in the majority, where the filibuster is a nuisance, or the minority, where it is a treasured right.
Republicans, who pondered the nuclear option a decade ago and opposed it in 2013, are now pushing it. And Democrats like Mr. Merkley, who four years ago thundered about the injustice of filibusters, are now begging for the tool to be preserved.
“When you look at how this is going to reverberate for the decades to come, it is really bad news for the Senate and it is terrible news for the courts,” Mr. Merkley told reporters as he left the Senate chamber after holding the floor for 15 hours in a mock filibuster.
The latest fight is over Judge Neil Gorsuch, who is President Trump’s first nominee to the Supreme Court. Judge Gorsuch has been designated to fill the seat of the late Justice Antonin Scalia.
Republicans say he is the perfect candidate, with tremendous legal credentials and a stellar career on the 10th U.S. Circuit Court of Appeals, where he established a record of agreement and careful scholarship.
Democrats have myriad objections. They fear he would overturn precedent establishing a right to abortion and precedent guaranteeing First Amendment political free speech rights while protecting corporate plaintiffs, and they say he would roll back established powers of the federal bureaucracy.
Some Democrats also say the entire nomination is tainted because it was made from a list Mr. Trump released during the election campaign, assembled with help from the conservative Federalist Society. Mr. Trump, they contend, shouldn’t be allowed to name a nominee while his campaign is under FBI investigation, and Judge Gorsuch is a fair sacrifice after Republicans blocked consideration last year of President Obama’s nominee, Judge Merrick Garland.
“We Democrats have principled reasons to vote against this nominee,” Senate Minority Leader Charles E. Schumer said. “We Democrats believe the answer isn’t to change the rules; it’s to change the nominee.”
Mr. Schumer acknowledged that both sides have reasons to blame each other for starting, or deepening, the rifts.
Some analysts trace the battles back to the 1980s, when Democrats voted not to confirm a conservative legal superstar, Judge Robert Bork, to the Supreme Court. After a two-decade lull, Democrats launched partisan filibusters of President George W. Bush’s appeals court nominees, beginning in 2003 with a respected Hispanic lawyer, Miguel Estrada.
They followed with filibusters of five other Bush judicial picks that year and added four other filibusters in 2004.
A year later, Republicans were poised to use the nuclear option and were derailed only after the so-called Gang of 14 senators — seven Republicans and seven Democrats — struck a compromise. Democrats agreed to approve most of the blocked judges in exchange for a promise from the Republicans not to support their party leaders’ plans to change the rules.
That truce held until 2011, when partisan power had shifted and President Obama was picking the judges. Republicans launched their first filibuster of an appeals court judge.
By 2013, Democrats said the obstruction was out of control and they looked to the nuclear option.
All told, some 40 Democrats who backed the nuclear option in 2013 are now poised to ignite another crisis by voting against Judge Gorsuch. Meanwhile, 38 Republicans who voted against the nuclear option in 2013 are ready to trigger it.
One senator who is maintaining consistency is Sen. Joe Manchin III, a West Virginia Democrat who voted against his party’s use of the nuclear option in 2013 and is expected to vote against Republican use of the tactic.
Mr. Manchin is supporting Judge Gorsuch’s nomination, saying he is more than qualified for the Supreme Court.
“He has been consistently rated as a well-qualified jurist, the highest rating a jurist can receive, and I have found him to be an honest and thoughtful man,” the senator said.
The decision is straining some longtime lawmakers, including Sen. John McCain, an Arizona Republican who was part of the Gang of 14. He was also instrumental in delaying the nuclear option early in 2013, though negotiations eventually broke down and Democrats did pull the trigger, reducing the filibuster for executive branch officials and lower-court nominees.
Mr. McCain said he warned Democrats at the time that the roles would be reversed someday and Republicans would use the nuclear option for Supreme Court nominees.
His frustration was evident this week as he lashed out at both sides, saying the Senate he has served in for 30 years has been “irreparably damaged” by the fights. He called those eager to trigger the nuclear option “idiots.”
Mr. McCain warned that the rules changes will push the federal courts more to the extremes on both the right and left and said the country is worse off for it. He called the situation heartbreaking but said he would join fellow Republicans in completing what Democrats started in 2013.
“I find myself torn between protecting the traditions of the practices of the Senate and the importance of having a full complement of justices on the U.S. Supreme Court,” he said. “I’m left with no choice. I will vote to change the rules and allow Judge Gorsuch to be confirmed by a simple majority.”