OXFORD DICTIONARY
comer, n.
1 a person who comes, esp. as an applicant, participant, etc. (offered the job to the first comer).
2 colloq. a person likely to be a success.
all comers any applicants (with reference to a position, or esp. a challenge to a champion, that is unrestricted in entry).
THESAURUS
comer
Young Turk, arrival, arriviste, bright young man, entrant, fledgling, immigrant, in-migrant, incomer, intruder, modern, modern generation, modern man, modernist, modernizer, neologism, neologist, neology, neonate, neoteric, neoterism, neoterist, new generation, new man, newcomer, nouveau riche, novus homo, parvenu, rising generation, settler, star, stripling, success, upstart, victor, visitant, visitor, winner