YOU SAID:

I could've been a contender.

INTO JAPANESE

私は競争相手になることができたでしょう。

BACK INTO ENGLISH

I could have been a competitor.

INTO JAPANESE

私は競争相手だったかもしれません。

BACK INTO ENGLISH

I may have been a competitor.

INTO JAPANESE

私は競争相手だったかもしれません。

BACK INTO ENGLISH

I may have been a competitor.