CLEVELAND, Ohio — In many ways, Marlean Ames’ lawsuit was fairly routine. The longtime employee of the Ohio Department of Youth Services said she was wrongly passed over for a promotion, demoted without an explanation from her bosses and lost out on some $40,000 a year.

The Supreme Court appeared virtually certain to side with an Ohio woman who lost a “reverse discrimination” suit against her employer when her gay boss declined to promote her, a decision that will likely make it easier for some White and straight employees to win similar claims.