Almost amusing
At the last leadership contest, following the resignation of Liz Truss, the Conservative 1922 Committe imposed a threshold saying any candidate would need to be nominated by 100 MPs to go forward to the ballot of members. This was designed to avoid the need for ballot of members. Sunak passed the threshold, Boris Johnson reportedly passed the threshold, but pulled out, and Sunak was elected unopposed.
If the Tories do get only 131 seats, as the exit poll suggests, then it would be impossible for more than one candidate to pass the 100-MP threshold.