WASHINGTON — Senate leaders say they are advancing long-overdue spending legislation for 2017 to avert both a government shutdown and a stopgap spending resolution before federal funding runs out on April 28.

But the Pentagon and hawkish lawmakers are taking no chances. The service chiefs plan to testify at the House Armed Services Committee April 5 on the consequences of the ongoing continuing resolution, which generally binds them to last year's spending levels and bars new-start acquisition programs.

"We are starting to get some of those preliminary indications, and it is very disturbing," said HASC Chairman Mac Thornberry, R-Texas, said of the ongoing CR's impact. "It seems to me we have an obligation to bring that out so that members will know what we're facing … We've already passed our [defense] appropriations, so I'd like to see some action on the other side of the Capitol."

The services, which are assessing the impact of extending the CR, are likely to argue that military readiness is suffering most. At a HASC hearing Tuesday, Marine Lt. Gen. Jon Davis, deputy commandant for aviation, said he would be forced under a year-long CR to cut all flying hours for six F/A-18 Super Hornet squadrons and four Harrier squadrons.

Senate Armed Services Chairman Sen. John McCain, R-Ariz., and Sen. Lindsey Graham, R-S.C., warned Tuesday that they would not vote for a long-term CR because it would harm the military. Instead they want an appropriations bill passed that increases military spending.

"The worst thing that could happen would be a CR," McCain said. "I will do everything in my power. I will not vote for a CR. I will not do that to the men and women in the military."

The defense industry, too, has been wary of a long-term CR, if not a shutdown. Robert Rangel, Lockheed Martin's top lobbyist and the former chief of staff for then-Defense Secretary Robert Gates, said he has seen "tremendous momentum across the board" to avoid a CR, but said, "I think we all have to be realistic that the threat of defaulting to a CR is there."

In a March 22 interview with Defense News, he said congressional deadlock and a CR this year would be a bad sign for 2018 defense spending, which the administration plans as the first step toward a promised defense buildup.

"In some respects you could look at it as, 'It's sort of an early test of the new political configuration.' If they don't figure this out in '17, it really makes the prospects for '18 that much tougher," Rangel said. "And of course the early outlines of the '18 budget suggest that this is going to be very, very difficult."

For the last eight years, Congress has been unable to pass timely appropriations and instead started the year on a continuing resolution. Amid fears Congress would deadlock yet again and extend the current CR to close out the fiscal year, which ends Sept. 30, lead senators were optimistic on Tuesday.

"There is no desire for a CR," Senate Majority Leader Mitch McConnell, R-Ky., told reporters. "Democrats and Republicans … are working together on this, and we fully anticipate getting it out by the end of April.

Sen. Roy Blunt, R-Mo., a junior member of the Senate GOP leadership, said a bipartisan group of lawmakers from both chambers is crafting a package that would include all remaining appropriations bills — but President Trump's politically charged supplemental spending request, and plan to fund it with non-defense cuts, would likely be tabled until a later date.

The comments came after the White House reportedly asked Congress for $18 billion in cuts to domestic programs to create headroom for a $30 billion supplemental spending request, which would fund defense and border security. Democrats are against the White House's approach on multiple fronts, including funding the supplemental by cutting domestic spending. Democrats also object because the request includes funding for a wall along the U.S.-Mexico border.

Senate Minority Leader Sen. Chuck Schumer, D-N.Y., said Democrats will be able to reach a deal to pass appropriations bills so long as sequestration isn't triggered, there is parity between defense and non-defense spending, and the bill has no partisan "poison pill riders."

"They do have to get our votes, given the divisions in their caucus and given how the Senate works. And so far, things are working out pretty well," Schumer said of Republicans, adding: "And I'm hopeful we laid those out way in advance that we can have the same success we had last year in coming up with a budget."

The normally taciturn chairman of the Senate Appropriations Committee, Sen. Thad Cochran, R-Miss., said Tuesday that defense appropriators were "making good progress" to avert a shutdown and a year-long CR.

"We're trying to do what's best for the economic and security interests for the country, make sure the bill is responsive to our genuine needs," Cochran said, adding: "We're not looking to shut anything down. We don't need to do [a year-long CR] either. We need to get the bill done, reconcile our differences."

Republican and Democratic committee leaders have been hashing out their appropriations bills, with plans to refer any issues they cannot resolve to House and Senate leaders. 

On Tuesday, Blunt said the plan most likely to work would be to use the $578 billion defense spending bill passed by the House last month as a legislative vehicle for as many appropriations bills as can be agreed to. But not the politically charged supplemental.

"All of the committees, House and Senate leadership, are working together to try to finalize the FY17 bill," Blunt said, using the abbreviation for fiscal year 2017. "My guess is it will come together better without the supplemental."

"The supplemental has to be dealt with differently because it is a different issue," he said. "The pay-for situation is different. It's a much smaller piece of defense. I think [Defense] Secretary [James] Mattis' priority is FY17."

Senators in both parties pushed back on Trump's supplemental request after details of the domestic offsets became public.

"I'm still waiting for the president to show he's going to build a wall with Mexican funding; That's what he promised us," Virginia Democratic Sen. Mark Warner told reporters. "The president made these promises, let's see him enact them."

Republicans Blunt and Graham separately told reporters they would not support the reported $1.2 billion cut to the National Institutes of Health, which was part of the offsets.

"I support defense increases, but I'm not going to support gutting the State Department and other programs," said Graham, who chairs the Appropriations Subcommittee on State, Foreign Operations, and Related Programs. "Soft power to me is as important as hard power. Developmental aid is part of the tools in the toolbox to protect the nation. NIH is a good investment. There is no way I'm going to vote to wipe it all out."

Whether the House side is matching plans with the Senate remains to be seen.

Asked about the supplemental, Rep. Kay Granger, the House Appropriations Defense Subcommittee chair, said Tuesday afternoon that she had not yet received direction from House leadership about the process or timing.

Thornberry said he has encouraged House appropriators to extend limits on funding provided by the supplemental beyond the current fiscal year's end on Sept. 30. He said he received no guarantees.

"What we don't want is to have a rush to spend money just to do it," he said. "So expanding that period would make sense."

Aaron Mehta  in Washington  contributed  to this report. 

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