In 1904, Samuel Gompers observed that progressive liberal public opinion was prompting employers to become more clandestine in their anti-union activities.

And he said he feared that the bill could increase insurance costs, prompting employers to discontinue coverage.

Opponents said it would prompt employers to discount merit as the basis for hiring and promotions.

In most of those states, insurers argued that expanding liability for health plans would lead to an increase in costs, prompting employers to reduce or eliminate coverage for millions of Americans.

Citing longstanding economic research, they said it did more harm than good, prompting employers to drop marginal workers not worth the higher minimum.

In the past, such shortages have prompted employers to push up wages to hire or keep qualified workers.

And the low unemployment rate has not yet prompted employers to train and hire high school dropouts from impoverished households, Mr. Sum said.

Further, studies show that Ellerth and Faragher prompted employers to "adopt or strengthen procedures for investigating, preventing, and correcting discriminatory conduct."

Mr. Benjamin said the weather might have prompted employers to hire summer workers in recreational industries and students on summer vacation earlier than usual.

The squeeze on profits from higher costs is prompting employers everywhere to cut hours, eliminate overtime and shed workers through layoffs.