Erin Kelly

USA TODAY

WASHINGTON — Senate leaders failed their first big test this week in their push to prove they can pass 12 spending bills and prevent the annual fiscal crisis that threatens to shut down the government at the end of the year.

After starting off strong last week with bipartisan consensus to pass a $37.5 billion energy and water bill, the process blew up when Sen. Tom Cotton, R-Ark., proposed an amendment Wednesday that Democrats charged was a "poison pill" that would undermine the Iran nuclear deal.

On Thursday, Democrats blocked the bill from advancing because of the amendment, leaving senators headed home for a weeklong recess without anything to show for two weeks of debate. The vote was 52-43 to advance the bill, falling short of the 60 votes needed.

The failure to advance the bill, which would pay for popular flood control projects, port improvements and nuclear safety programs, underscores just how difficult it will be for senators to pass the other 11 measures, many of which are much more controversial.

The vote was a blow to Senate Majority Leader Mitch McConnell, R-Ky., who had optimistically vowed to try to pass all 12 spending bills for 2017 by Oct. 1. Congress has not met that deadline since 1994. When Congress fails to pass the bills by the beginning of a new fiscal year, lawmakers are forced to scramble to put together one huge hodgepodge of a funding bill at the last minute to keep the government running.

McConnell's optimism was shared, at least briefly, by Democrats. Just a week ago, Sen. Barbara Mikulski of Maryland, the senior Democrat on the Appropriations Committee, said the bipartisan cooperation on the energy and water bill "signals that we are ready to do regular order ... so we don't end up with a big omnibus bill at the end."

"It is an excellent kickoff to what I hope will be the ability to move all 12 bills," she said on April 21.

But, on Thursday, Democrats and Republicans were back to blaming each other for the breakdown of the process.

"We now have a bipartisan opportunity to responsibly work through individual funding bills," said McConnell, who accused Democrats of "blowing up" the process for short-term political gain. "What it will take is for our Democratic colleagues to end this obstruction and work cooperatively across the aisle instead. That’s not too much to ask."

Senate Minority Leader Harry Reid, D-Nev., shot back, saying Democrats were ready to approve the bill until GOP leaders allowed Cotton to offer his amendment.

"We want to do appropriations bills," Reid said. "And we were on a rush to get one done, the first one. We were headed to victory, and out of nowhere comes a poison pill rider. And everyone acknowledges that's what it is ... Republicans should step back and figure out some other way to try to embarrass the president. This is not the way to do it."

Cotton's amendment would have barred the Obama administration from buying "heavy water" from Iran. The water is used in producing nuclear energy and weapons. As part of the nuclear deal reached between the administration and Tehran last year, Iran must reduce its supplies of heavy water so that it cannot produce nuclear weapons. Cotton, one of the most outspoken opponents of the Iran nuclear deal, said he wanted to stop U.S. money from going to subsidize a regime that has sponsored terror.

The White House said President Obama would veto the energy and water spending bill if it contained Cotton's amendment.

"We've made clear our commitment to a principle that ideologically motivated policy riders are not appropriate for appropriations bills," White House spokesman Josh Earnest said Wednesday.

It's not clear what the Senate's next step will be to try to get its spending bills back on track.

"This is a ridiculous place for the Senate to be,” McConnell said. "Ridiculous."

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