That last bit is key. If Republicans hope to spend additional money on defense over the next year, they'll need to pass a law through both the House and Senate that alters the Budget Control Act. Altering the defense spending caps is unlikely to be enough to earn the support of six Democrats in the Senate, much less President Obama's signature. That means that congressional negotiators will have to alter the caps for both defense and non-defense programs.
In the Senate, defense hawks appear to be open to the idea. And the fact that Enzi, unlike House counterpart Tom Price, has left the reserve fund open to defense and non-defense spending is a sign that a deal—however difficult—is possible.
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Republican Sen. Kelly Ayotte of New Hampshire, who has been a vocal supporter of raising the defense caps and opposed BCA when it passed in 2011, called the fund "an important first step" in overturning the sequester caps in a press conference with GOP leadership Tuesday—"if the Democrats want to work with us on a bipartisan resolution," she emphasized.
Ayotte is reportedly part of a working group that includes Sens. Lindsey Graham, Tim Kaine, Angus King, and Roger Wicker that has been discussing a potential solution over the last several weeks. Graham told The Hill that he would be willing to close certain tax loopholes in exchange for changes to entitlements in an ambitious agreement he termed "a mini Simpson-Bowles". So far, the group is still talking.
And although Sen. Patty Murray traded in her budget gavel for one on the Health, Education, Labor, and Pensions Committee this year, she's already pushing for another deal to end or alter sequestration.
Murray is pushing legislation that raises the caps by $74 billion in each of the fiscal years 2016 and 2017. The Washington state Democrat plans to introduce the bill as an amendment to the Senate budget later this week and will call on Republican colleagues to deal with the issue now, rather than waiting "until we get closer to another crisis," an aide said Tuesday.
(RELATED: Yet Again, House Republicans Are Stuck)
The Murray amendment is unlikely to pass through a Republican-controlled Senate, given that the offsets come from closing as-yet-unidentified tax loopholes on businesses and the wealthy, but the measure could be an early test of support for such a deal.
And Murray has said that she's open to other suggestions on how to pay for it. "If my Republican colleagues have any other ideas for how we get this done, my door is open, and I am ready to get to work," Murray said last week.
The House will be another issue. Leadership in the lower chamber is fighting fires between defense hawks who want to raise the caps, and fiscal conservatives who hope to maintain them, with a plan to vote Wednesday on a blueprint that boosts defense spending beyond the Budget Committee's original draft. And this is only in a symbolic budget document.
The battle lines being drawn in the House now will likely only deepen as Senate negotiators begin to discuss a possible sequestration deal. But if defense hawks are victorious in the House's budget fight Thursday, they'll gain important leverage for the sequestration fight down the road.