WASHINGTON • Democratic opposition to President Donald Trump's US Supreme Court nominee has grown even as the White House demanded a "fair, up-or- down vote" in the Senate on confirming Judge Neil Gorsuch to the lifetime post.
Four more Democratic senators on Monday added their support to a growing effort to block a confirmation vote through the use of a filibuster.
That procedural hurdle requires 60 votes in the 100-seat Senate to allow a confirmation vote by a simple majority.
Republicans control the Senate 52 to 48. There are now 20 senators who have backed Democratic leader Chuck Schumer's filibuster call - up from 16 last Friday.
Senator Joe Manchin, however, announced on Monday that he opposes a filibuster, according to an aide, and Senator Heidi Heitkamp also indicated she would oppose it. "It's my duty to fully consider any Supreme Court nominee, regardless of which party is in the White House," she said in a statement.
Democratic opposition to Judge Gorsuch could prompt a Senate showdown over the confirmation of the conservative appeals court judge from Colorado, but Republicans could change the Senate's rules to disallow filibusters against Supreme Court nominees.
Mr Trump is seeking to avoid another setback in Congress after major healthcare legislation he supported was pulled from the House of Representatives floor amid Republican opposition last Friday.
The confirmation of Judge Gorsuch, 49, to replace Justice Antonin Scalia, who died in February last year, would restore the nine-seat court's conservative majority, a major campaign promise for Mr Trump.
White House spokesman Sean Spicer said any attempted filibuster would be "nothing short of obstructionism".
The latest Senate Democrats to join the fight include Mr Bill Nelson, who said there are "real concerns" that Judge Gorsuch would be hostile to voting rights and support businesses over workers and consumers.
The other three Democratic senators to have newly announced their opposition were Judiciary Committee members Mazie Hirono, Al Franken and Jack Reed.
The committee is due to vote next Monday on sending the nomination to the full Senate.