WASHINGTON — House leaders on Monday unveiled a $1.4 trillion governmentwide spending bill that’s also carrying lots of unrelated provisions backed by the denizens of Washington’s swamp of lobbyists and interest groups.

Retired coal miners and labor union opponents of Obama-era taxes on high-cost health plans came away with big wins in weekend negotiations by top congressional leaders and the Trump White House. The bill would also increase the age nationwide for purchasing tobacco products from 18 to 21 and offers business-friendly provisions on export financing, flood insurance, and immigrant workers.

The legislation would forestall a government shutdown this weekend and give President Trump steady funding for his US-Mexico border fence. The year-end package is anchored by a $1.4 trillion spending measure that caps a difficult, monthslong battle over spending priorities.

The roster of add-ons grew over the weekend to include permanent repeal of a tax on high-cost “Cadillac’’ health insurance benefits and finance health care and pension benefits for about 100,000 retired union coal miners threatened by the insolvency of their pension fund. A tax on medical devices and health insurance plans would also be repealed.

The deficit tab for the package grew, as well — almost $400 billion over 10 years to repeal the three so-called Obamacare taxes alone — with a companion package to extend several business-friendly tax breaks still under negotiation. The Obama-era taxes have previously been suspended piecemeal.

Late-stage negotiations involved House Speaker Nancy Pelosi, Treasury Secretary Steven Mnuchin, and other top leaders. The package faces a House vote Tuesday, with the Senate expected to vote by Thursday or Friday.

The legislation is laced with provisions reflecting divided power in Washington. Republicans maintained the status quo on several abortion-related battles and on funding for Trump’s border wall. Democrats controlling the House succeeded in winning a 3.1 percent raise for federal civilian employees and the first installment of funding on gun violence research after more than two decades of gun lobby opposition.

The legislation, introduced as two packages for tactical purposes, is part of a major final burst this week, despite bitter partisan divisions and Wednesday’s likely impeachment of Trump. Thursday promises a vote on a major rewrite of the North American Free Trade Agreement, while the Senate is about to send Trump the annual defense policy bill.

The core of the spending bill is formed by the 12 annual agency appropriations bills. It fills in details of a bipartisan framework from July that delivers about $100 billion in agency spending increases over two years instead of automatic spending cuts that would have sharply slashed the Pentagon and domestic agencies.

Other add-ons include provisions sought by business and labor interests and their lobbyists in Washington.

For business, there’s a seven-year extension of the charter of the Export-Import Bank, and renewal of the government’s terrorism risk insurance program. The troubled flood insurance program would be extended through September, as would several visa programs for skilled and seasonal workers.

Labor won repeal of the 40 percent tax on high-cost employer health plans, originally intended to curb rapidly growing health care spending. But it disproportionately affected high-end plans won under union contracts.

Democrats won increased funding for early childhood education and a variety of other domestic programs, and higher Medicaid funding for Puerto Rico, which is struggling to recover from hurricane devastation and an economic downturn.

Most provisions in the bill enjoy bipartisan support, including increases for medical research, combating the opioid epidemic, and Head Start and child-care grants to states.

Democrats also secured $425 million for states to upgrade election systems, and boosted the US Census budget $1.4 billion above Trump’s request. They won smaller increases for the Environmental Protection Agency, renewable energy programs, and affordable housing.

“We are scaling up funding for priorities that will make our country safer and stronger and help hardworking families get ahead,’’ said the House Appropriations Committee chairwoman, Nita Lowey, Democrat of New York.

Because dozens of Democrats might vote against the border wall, Pelosi is pairing money for the Department of Homeland Security with the almost $700 billion Pentagon budget, which is guaranteed to win GOP votes to offset Democratic defections.

The coal miners’ pension provision had the backing of Trump and Senate majority leader Mitch McConnell of Kentucky.