Now that Republicans control Congress, they have largely agreed that they want to boost military spending at the expense of other domestic social programs. But they're at odds over how to do it.
Senate Republicans made clear Wednesday, in releasing their own fiscal 2016 budget blueprint, that they don't support the House GOP approach for hiking defense spending and prefer a different strategy.
Differences over military money, and other aspects of the Republican budgets -- including a Medicare overhaul -- risk leaving the GOP unable to pass their budget, something they criticized Democrats for failing to do when they controlled Congress.
The setback would derail not only the GOP goal of increasing the Pentagon coffers, but also other party priorities this year -- including the effort to repeal the Affordable Care Act.
"I'm absolutely confident we'll do our duty," said Sen. Roger Wicker of Mississippi, the head of the Republican Senate's campaign committee. "It's one of the most important votes we'll have this year."
Like the House GOP budget released earlier this week, the Senate plan for fiscal 2016 sticks to the party's mostly small-government principles: a robust military budget, alongside cuts to domestic safety net programs and no new taxes.
Both budgets adhere to caps agreed to in an earlier 2011 deal, and promise to balance within the decade -- though critics say those claims are exaggerated. And both fully repeal the Affordable Care Act.
But Republican senators were less willing than their House colleagues to fill in the specifics.
For example, the Senate promises to cut safety net spending for Medicare and the other programs, but the GOP senators declined the House's signature proposal for creating a voucher-like system for Medicare.
The Medicare overhaul, first introduced by Rep. Paul Ryan (R-Wisc.), the former GOP vice presidential candidate, has never been fully embraced by Senate Republicans. It would substantially change Medicare for those who reach retirement age in 2024.
The defense proposals both promise to raise military spending, while adhering to limits established under the 2011 deal -- a political pretzel that deficit hawks among the GOP say they will have difficulty supporting.
The House GOP increases defense spending by adding money to a separate war account that was not covered under the 2011 deal. Senators establish a new fund that could become a receptacle for additional Pentagon money, if cuts could be made elsewhere.
Neither appears likely to satisfy the other side -- or the most fiscally conservative Republicans in their ranks -- making agreement difficult.
If Congress is unable to approve a budget, it would not be able to take advantage of special budget rules that would allow it to pass other bills -- like a repeal of the Affordable Care Act -- by a simple majority that could overcome a Senate filibuster.
Senate Majority Leader Mitch McConnell (R-Ky.) struck an upbeat tone Wednesday as his side of the Capitol unveiled its spending plan, in stark contrast to what he called the "unserious budget" released by Obama earlier this year. The majority headed by House Speaker John A. Boehner (R-Ohio) released its budget Tuesday.
"It's a rite of passage," said Sen. Bob Corker (R-Tenn.) "Hopefully, that will be an opportunity for us to showcase some success."
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