Publicity given to electric car using artificial intelligence at lavish opening, should hold sway (7)
I believe the answer is:
prevail
'sway' is the definition.
(thesaurus)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for prevail that I've seen before include "Win through" , "Be current" , "Prove more powerful" , "Be victorious" , "Exist generally" .)