WASHINGTON — Congress reconvened Monday with leaders in a rush to close out a $1.1 trillion spending plan, but Republicans and Democrats are on a collision course over dozens of policy riders that lawmakers want to attach to the must-pass spending measure.
The fight — over issues as varied as clean-water regulations, conflict-of-interest rules for financial advisers, and size limits for trucks on federal highways — raises a small, but real, risk of a government shutdown if no accord is reached by a Dec. 11 deadline.
Speaker Paul D. Ryan of Wisconsin and the Senate majority leader, Mitch McConnell, R-Ky., said amendments would be attached to the spending measure, while the White House and Democrats denounced the riders as "poison pills."
Some Democratic lawmakers said concessions were inevitable, provided that Republicans did not push items such as a repeal of President Obama's health care law or a cutoff in financing for Planned Parenthood, an effort that the president has made clear he would veto.
While Republican leaders appeared to be taking steps to avoid a stalemate over the most highly charged proposals, including repeat fights over the health care legislation, lawmakers noted that a serious breach was still possible on more mundane topics.
"It still takes a presidential signature at the end of the day," said Representative Tom Cole, R-Okla., one of the so-called cardinals on the House Appropriations Committee. "And both sides have got to provide votes for this thing."
With most of the Capitol shut last week for the Thanksgiving recess, negotiators worked nearly round the clock in a basement conference room to divvy up the roughly $66 billion in additional spending for 2016 that was part of a landmark bipartisan budget deal in October. The amount includes roughly $33 billion in discretionary spending on domestic programs.
That budget deal, brokered by the departing House speaker, John A. Boehner, R-Ohio, substantially limited the prospect of a government shutdown by setting top-line spending limits for 2016 and 2017, and averted a potentially disastrous default on the debt.
The seeming breakthrough nature of the deal obscured deep divisions: Most Republicans in the House and Senate voted against the accord, and Ryan, in his new role as speaker, has less to gain from forcing even a minority of his rank-and-file into a pact with Democrats.
Ryan already chalked up some early victories, including swift passage of a bill to suspend the Obama administration's plans to admit more Syrian refugees — a measure that won over a surprising number of Democrats despite White House lobbying against it.
The refugee measure, which is likely to be blocked by a Democratic filibuster in the Senate, could be repackaged as a policy rider on the overall spending measure, which is a compendium of the 12 individual appropriations bills that Congress is supposed to adopt each year.
Among the most controversial policy riders are proposals that the Obama administration opposes but that have at least moderate bipartisan support in Congress.
They include a bid by lawmakers from farm states to block new federal clean-water rules; an effort, backed by shipping companies, to allow longer tandem trucks on federal highways in all states; and an effort, supported by the financial industry, to prevent new conflict-of-interest provisions for investment advisers who manage retirement funds.
A Senate Democratic aide said that Ryan; McConnell; the House Democratic leader, Nancy Pelosi of California; and the Senate Democratic leader, Harry Reid of Nevada, had begun negotiations.
Democrats and the White House had hailed the late October budget accord as a victory because it broke through previously agreed-upon budget caps that Democrats said were causing a major drag on the economy — and because the deal provided for an equal increase in military and nonmilitary spending.
But the budget deal only set the spending limits; it did not set spending on specific programs. And in that decision-making, Republicans who control the majority in each chamber in Congress, have had far greater sway, according to lawmakers from each party.
That has meant more money for veterans' programs, for instance, and less for rental assistance and other social-welfare benefits for the poor.
Representative Rosa DeLauro of Connecticut, the senior Democrat on the Appropriations subcommittee that oversees labor programs and health and human services, said too few of the new dollars approved in the budget accord were being directed by Republicans to needy Americans.
"Labor-HHS is 32 percent of nondefense discretionary funding — that translates into $10.5 billion," DeLauro said. "Our allocation is $5.2 billion."
Cole, chairman of the subcommittee, said Democrats were unwilling to choose priorities and accept necessary cuts.