1. （职位的）觊觎者，冒充者
A pretender to a position is someone who claims the right to that position, and whose claim is disputed by others.

1. a person who professes beliefs and opinions that he or she does not hold in order to conceal his or her real feelings or motives

Synonym: hypocritedissemblerdissimulatorphonyphoney

2. a person who makes deceitful pretenses

Synonym: imposterimpostorfakefakerfraudshamshammerpseudopseudrole player