Former Montana state Sen. Corey Stapleton confirmed to CQ Roll Call on Tuesday that he is dropping his Senate bid to run for the House instead.

“It’s official,” he said by phone.

The exit of the last remaining Republican in a top pickup opportunity for the GOP is the latest indication that Rep. Steve Daines will run for the open Senate seat.

Stapleton appeared to let Daines’ decision slip in an earlier interview with Montana’s Lee Newspapers. But Daines spokeswoman Alee Lockman said the congressman hasn’t “made any final decision yet” and still does not have a timeline to do so.

Daines has been widely expected to make the leap since Democratic former Gov. Brian Schweitzer announced in July that he was not running. But the freshman Republican has only said publicly that he was giving it serious consideration.

Democrats are still in search of a candidate to vie for the seat of retiring Sen. Max Baucus, whose exit left a vulnerable open seat. Lt. Gov. John Walsh and state Supreme Court Justice Brian Morris are often mentioned as potential candidates.

A Daines Senate bid would set off a crowded race for the state’s lone House seat. Before Stapleton’s decision, state Rep. Champ Edmunds and state Sen. Matt Rosendale said they would run for the House if Daines runs for Senate. On the Democratic side, former Baucus aide John Lewis is running.