A delegate can be de-certified for a number of reasons, including not being a registered voter or not being a resident of the state where he or she was selected. The Committee on Contests reviews each contested delegate individually.

“You’re going to have 4,400 delegates show up and vote on a nominee, and in some way or another you have to decide: Who are these people?” explained one Republican official familiar with the process.

The impact of such challenges could have a monumental bearing on the nomination in the event of a second ballot, potentially replacing delegates favorable to one candidate with alternates favorable to another.