If you describe someone as an also-ran, you mean that they have been or are likely to be unsuccessful in a contest. someone who fails to win a competition, election etc
one who loses a competition, contestant that does not win (Sports); candidate who loses an election (Politics); one who is unsuccessful or unimportant
[ -"ran ] (noun.) 1896. The phrase comes from the world of horse race betting wherein lists of winners would be published with all non-paying positions printed in a block under the heading 'Also Ran:'.