Senate Majority Leader John Thune is confronting an intensifying intra-party backlash after Speaker Mike Johnson’s rejection of a Senate deal to fund the Department of Homeland Security handed President Donald Trump and hardline GOP senators fresh leverage to press him to end the chamber’s two-week recess and abandon the filibuster.
Thune’s split with Johnson over DHS funding has exposed the South Dakota Republican to pressure from all directions, according to aides and GOP senators interviewed. The White House has privately warned that it is unsustainable for the Senate to remain out of session for two weeks while DHS remains unfunded. Trump has used the impasse to renew his campaign to erase the filibuster, pressing Thune directly in phone calls on Sunday and again on Monday, people familiar with the conversations said.
Hard-right Republicans — including Sens. Mike Lee (R‑Utah) and Rick Scott (R‑Fla.) — have urged Thune to reconvene the Senate immediately and consider changing Senate rules to force through priorities like the SAVE America Act. “What do DHS funding and the SAVE America Act have in common? A lot,” Lee said, arguing both have been harmed by the chamber’s willingness to recess while urgent business lingers. Several senators told reporters there is a growing sense that Trump is using the DHS standoff as a pretext to push the GOP toward nuking the filibuster.
Thune, who has acted as a consistent check on Trump’s institutional assaults since becoming Senate GOP leader 15 months ago, now faces a test of that posture. His allies say he feels “thrown under the bus” by Johnson’s decision to spurn the unanimous Senate agreement with Democrats intended to avert a shutdown at DHS, and by insinuations that Thune secretly cut a deal with Senate Minority Leader Chuck Schumer. Those allies pointed out that senators who have criticized the deal could have voted against it on the Senate floor but did not, and that no Republican showed up for Monday’s pro forma session to press the chamber back into action.
Thune has also shifted on one point: he is less skeptical of pursuing a second budget reconciliation vehicle to fund Immigration and Customs Enforcement and Customs and Border Protection after Johnson’s move sapped momentum for other legislative options. But even with that change, Thune has resisted calls to reconvene the Senate simply to stage “show votes,” telling GOP senators on Sunday that breaking the pro forma schedule requires unanimous consent and, in his view, should be reserved for when there is a substantive path forward.
Sen. John Hoeven (R‑N.D.) defended Thune’s handling publicly, calling him “absolutely” up to the task, while acknowledging that the filibuster protects conservative policies and must be weighed carefully. Hoeven said GOP leaders were still exploring whether they could reach a unanimous-consent agreement with Democrats before the next pro forma sitting on Thursday, though several Republican senators described that prospect as unlikely and said the most straightforward path would be for the House to take up the Senate’s bill.
The political optics have become a headache for Republicans: with DHS operations constrained, critics have pointed to social-media posts and outlets such as TMZ running images of lawmakers on vacation while the agency’s funding hangs in limbo. For Thune, who has so far been the GOP’s institutional firewall, the episode marks a potential turning point — balancing his long-standing defense of Senate norms against mounting demands from the White House and insurgent Republicans to act immediately.