I asked around about this Tuesday afternoon while Senate Democrats and Republicans met with their respective caucuses for weekly policy lunches. At the moment, such negotiations are being very tightly held, if they're occurring at all.
"I'm not aware of any," said Sen. John Cornyn (R-TX).
Senate Majority Leader Harry Reid (D-NV) joked that if he revealed the existence of any discussions, "they wouldn't be back channel."
At a Wednesday press conference, Reid said Senate appropriators would put together their own spending package in the coming days as a counterpoint to the House legislation. And Reid's top deputy Dick Durbin (D-IL) said he's unaware of any top-level negotiations between House and Senate leaders.
When the stakes are really high, and members of the two different caucuses have wildly different priorities, it's not uncommon for the principals to take matters into their own hands and reach a take-it-or-leave-it agreement that neither side really likes that much. It happened in December during the tax cut fight, when Senate Minority Leader Mitch McConnell (R-KY) came to an agreement with the White House while reporters staked out largely meaningless "official" negotiations on the Hill.
Something similar could happen here. McConnell touched on this phenomenon briefly during his weekly press conference Tuesday afternoon.
"It doesn't have to be in public," he said. "We all understand there's some limitations to negotiating significant agreements in public."
He was talking about entitlement reform, but the point stands for an agreement that could forestall a government shutdown.