That’s because most Senate Republicans can vote against the measure with impunity, knowing that it’s likely to pass with overwhelming support from Democrats and a smattering of their GOP colleagues in safe seats. Senate Republicans can publicly bemoan the shortcomings of the deal and complain that it doesn’t address entitlement spending and lacks a long-term blueprint to reduce the deficit. In short, they can sound just as exasperated with the budget agreement as their tea-party challengers and conservative critics.

But, assuming the measure passes, they can also avoid fallout over a government shutdown like the one in October, which badly hurt the GOP in opinion polls. “We took the brunt of the shutdown blame,” said a senior GOP aide. “No doubt—it’s a good thing for us.” Put another way, if Senate Republicans blocked the budget agreement, they would play into what a senior Democratic aide called “one of our favorite narratives on them,” obstructionism. “I don’t think anybody on either side wants a government shutdown,” said Sen. John Boozman, R-Ark. “We need to get this behind us.”

One reason GOP senators are getting a pass this time has to do with how the budget deal was put together. The lead negotiators, Sen. Patty Murray, D-Wash., and Rep. Paul Ryan, R-Wis., were intent on reaching an agreement they could sell to their respective caucuses. Not surprisingly, Senate Democrats have supported Murray by rallying behind the plan. Although not as united, key members of the House Republican Conference also lined up behind Ryan and voted for the deal Thursday. The process left Senate Republicans on the sidelines.