Washington(CNN) Within minutes of President Donald Trump's selection of Neil Gorsuch to the Supreme Court, Democrats who will lead the fight in the Senate delivered scathing assessments -- but held fire on perhaps the most important question facing them: whether they will filibuster the nomination.
Senate Democratic Leader Chuck Schumer immediately said he had "serious doubts" about Gorsuch and hinted at a Democratic filibuster, saying the nominee would need to the support of 60 senators to be confirmed, but stopped short of committing to the tactic.
"Make no mistake, Senate Democrats will not simply allow but require an exhaustive, robust, and comprehensive debate on Judge Gorsuch's fitness to be a Supreme Court Justice," Schumer said Tuesday night.
On the surface, Senate Democrats stuck to a firm but somewhat noncommittal message that hinted at the behind-the-scenes debate at the Capitol over whether Democrats will filibuster.
If they choose to hold up his nomination unless he can win 60 votes, Democrats risk spurring Republicans to use the "nuclear option" to rewrite the rules to only require 51 votes for confirmation.
Republicans hold a 52-48 majority in the Senate, meaning they would still need to find the support of eight Democrats without the nuclear option.
It's possible moderate Democrats facing tough re-election battles could be plucked away by Republicans to support Gorsuch. Sen. Heidi Heitkamp, a North Dakota Democrat, and Sen. Joe Manchin, a West Virginia Democrat, issued muted statements Tuesday night.
"I look forward to meeting with Judge Gorsuch, examining his record, and making a determination of whether to provide my consent. Just as I have all along, I urge my colleagues to put partisan politics aside and allow the vetting process to proceed," Manchin said.
And Sen. Angus King, an independent from Maine who votes with Democrats, hesitated to go after Gorsuch, saying he wants the nominee to go through a thorough vetting before making a decision.
Democrats, meanwhile, are already facing intense pressure from a liberal base fired up after Trump's inauguration, the immigration ban and a perception that some senators, including Schumer, have been soft on Trump's Cabinet picks.
House Democratic Leader Nancy Pelosi, a veteran liberal from San Francisco, laid out her opposition in stark terms at a CNN town hall Tuesday night.
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"If you breathe air, drink water or eat food, take medicine or in any other way interact with the courts, this is a very bad decision -- well outside the mainstream of American legal thought," Pelosi said.
Top Democrats on the Senate Judiciary Committee, who will spend the coming months vetting (and potentially blocking) Gorsuch announced "deep concerns" with his selection.
"I have deep, serious concerns about Judge Gorsuch," said Sen. Richard Blumenthal, a Connecticut Democrat. "An extreme ideologue on the court will threaten privacy rights including women's health care, worker and consumer protections, and public health and safety."
And Sen. Patrick Leahy, the former chairman of the Senate Judiciary Committee who shepherded President Barack Obama's two nominees on to the high court, sought to hang Trump's immigration ban around Gorsuch's neck immediately.
"In light of the unconstitutional actions of our new President in just his first week, the Senate owes the American people a thorough and unsparing examination of this nomination," Leahy said.
Texas Republican Sen. Ted Cruz hinted at the idea of cracking open the "nuclear option" if Democrats when asked how Republicans should respond to a filibuster.
"The Democrats will not succeed in filibustering Judge Gorsuch," Cruz told CNN's Jim Acosta.