Also threatening Democrats: the very real possibility that if they do try to block Gorsuch, a conservative 49-year-old federal appeals court judge with sterling credentials, Republicans will use their narrow Senate advantage to unilaterally change the rules and push through his nomination with a simple majority vote, instead of the 60 now required.
The dynamics offer no clear end game for Democrats, putting them on defense and Republicans on offense for the first time in Trump's presidency. "It is not easy for any of us," said Democratic Sen. Tom Carper of Delaware, noting that in addition to anger over Trump, many Democrats are still smarting over the treatment last year of former President Barack Obama's Supreme Court nominee, Judge Merrick Garland, who never got a hearing from Republicans as they held the Supreme Court vacancy open for the next president to fill.
"There are a lot of folks in my state and states across the country who are still outraged," Carper said. Senate Republicans, who'd been rattled over the rocky start to Trump's presidency, are now girding for a fight on their territory and their terms, one they feel quite confident they will win.
"It feels good to have a candidate that all of us can feel proud of. And I think you'll probably see some Democrats give him the benefit of the doubt," said GOP Sen. Rob Portman of Ohio. "I think he's a tough person to oppose on the basis of qualifications. I just don't see any opening there."
Despite Gorsuch's credentials, including experience as a clerk to Justice Anthony Kennedy, a number of progressive groups have already announced their opposition. Among other things they cite his opinions in favor of "religious liberty" exemptions for private companies that don't want to provide contraception coverage under federal law.
Groups including the Progressive Change Campaign Committee are keeping close track of what Democratic senators are saying about Gorsuch, praising those who've already announced their opposition to him while issuing veiled threats against any who haven't, and swamping phone lines on Capitol Hill.
"Any red state Democrat who thinks that it's smart to be weak in the face of Trump's unconstitutional agenda is lining themselves up for defeat in 2018," said Adam Green, the PCCC's co-founder. Green said his group will be pressuring Sen. Chris Coons, D-Del., after Coons told reporters that Gorsuch deserved a hearing and a vote in committee.
Democratic Sen. Claire McCaskill of Missouri, who is up for re-election next year, came under attack after saying over Twitter that any Supreme Court nominee should have a full confirmation hearing and a vote. She tried to defend herself in subsequent tweets, including one that read: "Why would anyone think that because I support confirmation hearing &60 vote threshold for SupCt nominee that means I'm folding to Trump?"
Protesters have swarmed Senate Minority Leader Chuck Schumer's home in Brooklyn, New York, to demand that he stand strong against Gorsuch and other elements of Trump's agenda. "People are very very active, very engaged," said Sen. Gary Peters, D-Mich., adding that many of his liberal supporters would like to see him come out against Gorsuch now, before he even has a hearing. "There's certainly a lot of folks that would like that, but I take my job very seriously, which means you have to be thoughtful and collect facts and then make a decision."
Democrats who've already weighed in against Gorsuch, like Jeff Merkley of Oregon and Elizabeth Warren of Massachusetts, are doing so without having met with him. The judge has met with only one Democratic senator so far, Joe Manchin of West Virginia, who's seen as the likeliest "yes" vote in the 48-member Democratic caucus. Gorsuch will meet on Monday with Sen. Dianne Feinstein of California, the top Democrat on the Judiciary Committee, and hearings in that committee are expected to start in about six weeks.
Schumer has tried to walk a fine line satisfying the liberal base while also giving space to red-state Democrats by insisting that Gorsuch should get 60 votes in the Senate, the level needed to end a filibuster, without specifically threatening a filibuster.
As for the "nuclear option" of changing Senate rules and eliminating the filibuster for Supreme Court nominees, McConnell has been noncommittal even as Trump himself has backed the scenario. The tactic has recent precedent: Democrats themselves, while in the majority in 2013, eliminated the filibuster for all nominees except potential Supreme Court justices. That change is now allowing Trump to get his Cabinet confirmed.
But the very possibility seems to create a no-win scenario for Democrats: lend eight votes to put Gorsuch on the court, infuriating their base; or oppose the judge with a filibuster, potentially angering swing voters and forcing McConnell to "go nuclear."
"For a lot of voters in these red states, the future of the Supreme Court was a galvanizing issue," said Steven Law, head of a McConnell-backed Super PAC that helps elect Senate Republicans. "Democrats who try to obstruct this president's choice for the court will face the same voters' wrath next year."