McConnell endorsed a sweeping GOP plan that fulfills Trump’s calls to legalize the status of 1.8 million “dreamers,” spends at least $25 billion to bolster defenses along the U.S.-Mexico border, makes changes to family-based legal migration programs and ends a diversity lottery system used by immigrants from smaller countries.

The Secure and Succeed Act is “the only piece of legislation that can get through the Senate, through the House of Representatives, most importantly signed by the president,” said its lead sponsor, Senate Judiciary Committee Chairman Charles E. Grassley (R-Iowa).

But no Democrats are believed to back the plan in full — and Sen. Richard J. Durbin (D-Ill.) described it as “an all-Republican measure.”