WASHINGTON — Congress may have passed a budget resolution last week, but Democratic leaders say they are girding for a possible confrontation with Republicans over the omnibus spending bill after their Republican counterparts refused to rule out legislative policy riders.

Just as the Pentagon and defense industry were able to breathe a sigh of relief over the budget deal, which gives the Defense Department nearly everything it wanted, Democratic leaders insisted that controversial policy riders — "poison pills" — would cost their support and could lead to a government shutdown.

"There are things they want to do like repeal Obamacare, go after Planned Parenthood, that the president would literally veto, putting us back in the soup without a resolution to this problem," Assistant Senate Minority Leader Sen. Dick Durbin, D-Ill., said of congressional Republicans. on Tuesday.

Beyond the budget deal, which eased sequestration budget caps for and suspended the debt ceiling for two years, House and Senate appropriators will need to pass an omnibus spending bill, or 12 appropriations bills, by Dec. 11, to prevent a government shutdown. 

Senate Minority Leader Sen. Harry Reid and Democratic leaders in the Senate voiced fears that Republicans, who offered little support for the budget deal, will use controversial riders to try to derail it.

"Democrats stand united against any shutdown riders that have no chance of being signed into law," Reid, D-Nev., told reporters. "We've been in touch with the White House this morning and the president agrees with what we plan to do."

The comments came after Senate Majority Leader Sen. Mitch McConnell, R-Ky., and House Speaker Rep. Paul Ryan, R-Wis., McConnell separately refused to rule out another confrontation with Democrats over riders.

"This is the legislative branch and the power of the purse rests within the legislative branch, and we fully expect that we're going to exercise that power," Ryan said.

Senate Majority Leader Mitch McConnell, who has previously vowed there would be no government shutdown, downplayed the issue’s significance.

"Riders in appropriations bills are quite common," McConnell told reporters. "The Democrats will have some, too. Of course, there will be some riders in the appropriation bills."

Reid suggested that Senate Democrats wouldn't pursue their own riders. Asked what riders Democrats are considering, Reid he told reporters, "we're not looking for riders."  

Otherwise, Reid was optimistic about the appropriations process.

"I'm confident that if we move and the Republicans work with us to get an omnibus bill done, I think we can work out the poison pill riders they've been talking about," he said.

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