5 things that could trip up the spending bill

• Immigration: This is the biggest danger. Democrats will push hard for legal status for the "DREAMers" — people who are in the country illegally who came here as children. And there's no sign that Republicans are willing to put it in the year-end bill. "I don't see how a majority of this Congress leaves without some resolution," said Jim Dyer, a former House Appropriations Committee Republican staff director.
• No tax deal before the spending bill: If Republicans can't pass a final version of the tax bill by Dec. 22, President Trump could easily pressure Congress to stay in town by refusing to sign a government funding extension until lawmakers finish the tax bill.
• Defense vs. domestic spending: Democrats could make trouble if a funding bill includes a big boost for defense spending, but nothing for domestic programs.
• CHIP funding: The Children's Health Insurance Program has expired, and Republicans had said the year-end bill was where its funding would be extended — but they still haven't figured out how to pay for it. Expect pushback from Democrats, and maybe governors, if it doesn't happen.
• ACA payments: Republican Sen. Susan Collins wants two fixes for the Affordable Care Act — a bipartisan renewal of payments for insurers and a separate set of "reinsurance" funds — as a condition for her to vote for a final tax bill. That could cause problems if the House doesn't go along, which it probably won't.

One more thing: A larger problem, Dyer said, is "the general level of rhetorical excess" — partly driven by the White House.

• His point: Most of the problems are solvable. It just takes cooler heads.