WASHINGTON, United States (AP) — A divided Senate rejected a bipartisan plan Thursday to help young “Dreamer” immigrants and parcel out money for the wall President Donald Trump wants with Mexico, as Republican leaders joined with the White House and scuttled what seemed the likeliest chance for sweeping immigration legislation this election year.

The vote came after the White House threatened to veto the measure and underscored that the issue, a hot button for both parties, remained as intractable as it’s been for years. Even the focus on Dreamers, who polls show win wide public support, was not enough to overcome opposition by hard-line conservatives and liberal Democratic presidential hopefuls — neither of whom want to alienate their parties’ base voters.

The vote was 54-45 in favour, but that was short of the 60 that were needed for approval. Eight Republicans bucked their party and supported the measure while three Democrats abandoned their own leaders and opposed it.

The chamber planned to vote next on a wide-ranging plan by Trump that would also restrict legal immigration. It faced strong Democratic opposition and had virtually no chance for passage.

Earlier Thursday, the White House used a written statement to label the proposal “dangerous policy that will harm the nation.” It singled out a provision that directs the government to prioritise enforcement efforts against immigrants who arrive illegally beginning in July.

In an ominous sign, party leaders opened the day’s debate by trading blame, as prospects grew that the chamber’s long-awaited debate on helping Dreamers and other hot-button immigration issues would end in stalemate. Dreamers are young immigrants who were brought to the US illegally as children who still lack permanent protections from deportation.

Senate Majority Leader Mitch McConnell, assailed Democrats for failing to offer “a single proposal that gives us a realistic chance to make law.” Instead, he said, Democrats should back Trump’s “extremely generous” proposal.

Trump would offer 1.8 million Dreamers a 10- to 12-year process for gaining citizenship, provide US$25 billion to build his coveted US-Mexico border wall and restrict legal immigration. Dreamers are immigrants brought to the US illegally as children who risk deportation because they lack permanent authorisation to stay in the US.

Instead, Democratic leaders rallied behind a bipartisan plan that would also give 1.8 million Dreamers a chance for citizenship. But while it would provide the US$25 billion Trump wants for his wall, it would dole it out over 10 years and lacks most of the limits Trump is seeking on legal immigration.

Senate Minority Leader Chuck Schumer said Trump has “stood in the way of every single proposal that has had a chance of becoming law.” He added, “The American people will blame President Trump and no one else for the failure to protect Dreamers.”

Overnight, the Department of Homeland Security said in an emailed statement that the bipartisan proposal would be “the end of immigration enforcement in America.”

That drew fire from Senator Lindsey Graham, one of eight GOP co-sponsors of the bipartisan plan. “Instead of offering thoughts and advice — or even constructive criticism — they are acting more like a political organisation intent on poisoning the well,” Graham said in a statement.

The bipartisan compromise was announced Wednesday by 16 senators with centrist views on the issue and was winning support from many Democrats, but it faced an uncertain fate.

Besides opposition by the administration and leading Republicans, the bipartisan plan prompted qualms among Democrats. The party’s number 2 Senate leader, Dick Durbin of Illinois, said some Democrats had “serious issues” with parts of the plan. Those concerns focused on its spending for Trump’s wall and its prohibition against Dreamers sponsoring their parents for legal residency.

So far, neither Trump’s plan or the bipartisan measure seemed to have support from 60 senators, the number that will be needed to prevail. Republicans control the chamber 51-49, though Senator John McCain, has missed the last several weeks while battling cancer.

The bipartisan measure’s sponsors included eight GOP senators. That meant just three more Republicans would be needed for it to prevail if it is backed by all 47 Democrats and the two independents who usually support them.

The centrist proposal was produced by a group led by Senators Susan Collins and Joe Manchin that spent weeks seeking middle ground. Besides its path to citizenship and border security money, it would bar Dreamers from sponsoring their parents for citizenship, far narrower than Trump’s proposal to prevent all legal immigrants from bringing parents and siblings to the US.

The moderates’ measure does not alter a lottery that distributes about 55,000 visas annually to people from diverse countries. Trump has proposed ending it and redistributing its visas to other immigrants, including some who are admitted based on job skills, not family ties.

Also in play is a more modest plan by McCain and Senator Chris Coons. It would let many Dreamers qualify for permanent residency and direct federal agencies to more effectively control the border by 2020. But it doesn’t offer a special citizenship pathway for Dreamers, raise border security funds or make sweeping changes in legal immigration rules.

The White House said it opposes the McCain-Coons plan, saying it would “increase illegal immigration” and cause other problems.

Another vote would be taken on a proposal by Senator Pat Toomey that would add language blocking federal grants to “sanctuary cities,” communities that don’t cooperate with federal efforts to enforce immigration laws. The amendment is considered sure to lose.