The Heritage Foundation has approached one of the Senate’s leading anti-Trump Republicans, Ben Sasse, to gauge his interest in serving as president — an indication the influential conservative think tank may turn away from its supportive posture toward the president.

Sasse, who was elected to his first term in the Senate in 2014, has swatted down the overtures from Heritage’s board of directors, according to two sources familiar with the recruitment effort. The Nebraska senator rose to national prominence when he announced early in the primary calendar that he would support neither Donald Trump nor Hillary Clinton, and he has been a persistent critic of Trump ever since.

The entreaties are one sign that Heritage may be looking to change course after the May ouster of its former president, Jim DeMint. In the Senate, DeMint was a leading antagonist of establishment Republicans, and at Heritage he suffered from the perception that the organization was becoming too political — and too reflexively pro-Trump — as its focus on scholarship fell by the wayside.