The Senate next week will continue, and perhaps finish, work on its 2016 Pentagon policy bill. The House could take up its defense appropriations bill, according to a senior aide. As both measures move toward final passage, Republicans essentially are calling President Barack Obama's bluff. That's because the White House continues to warn that unless members change major provisions opposed by Democrats and Obama, the president will veto the final 2016 defense bills. So keep an eye on floor proceedings for any amendments aimed at avoiding what could become a very messy summer.

Issue: OCO's Base Funds

Background: Republican leaders in both chambers added $38 billion to the Obama administration's $50.9 billion overseas contingency operations (OCO) account. The idea was to appease vocal defense hawks by giving the Pentagon more monies, even if no one really likes allocating base-budget funds within the war account, which is not subject to the 2011 Budget Control Act's spending caps. Obama and his top budget lieutenants have said for months he would veto any spending legislation that adheres to the defense and domestic caps, or any defense bill with additional dollars if there was no domestic hike on the horizon.

What To Watch: Senate Minority Leader Harry Reid, D-Nev., told reporters June 2 the White House is serious about President Barack Obama's promises on federal spending. "The president said he's going to veto it, so I think it really is kind of a waste of time," Reid said of Majority Leader Mitch McConnell's decision to bring up the bill. "We'll see what happens." Unless the inflated OCO and other provisions in the Senate's defense authorization bill are changed, the White House says "the president's senior advisers would recommend to the president that he veto it." Would Obama really veto a bill with so many provisions that are important to US military personnel? Some defense sources doubt it, but the timing of the Senate's action suggests GOP leaders are building in time to try again on the bill if he does. Since the swollen war fund also is in the House's defense appropriations measure, it also is at risk of being vetoed.

Issue: Democratic Amendments

Background: Just how the Senate floor proceedings on the NDAA will play out remains murky. SASC Chairman John McCain, R-Ariz., and other GOP leaders say they can push the bill through, perhaps as soon as late next week. During the last few years, when Democrats controlled the chamber, Republicans held up the legislation over complaints that then-Majority Leader Harry Reid, D-Nev., blocked floor votes on many of their amendments. Republicans are in charge now. Hundreds of amendments are expected to be filed. The chamber cannot debate and vote on all of them, with other items to get off the docket.

What To Watch: How will Democrats react when McConnell and McCain inform them their favorite amendment won't make it to the floor? Will they filibuster and sink the bill? They're playing coy -- for now. Rank-and-file Democrats for years defended Reid's practice of "filling the tree," as it's called on Capitol Hill. GOP ire at the practice has several times put a 53-year streak of final passage of the NDAA at risk. So how will Democrats react to anything short of an open rule on floor amendments? Over in the House, keep an eye on potential attempts by an alliance of conservative Republicans and liberal Democrats to push through amendments on the defense spending bill to shrink the war fund to levels more acceptable to the White House.

Twitter: @BennettJohnT