When the Republican Party formed in the 1850s, its support for free labor meant that

In the 1850s, “free labor” meant labor by people who were not enslaved and could choose their work. Republicans opposed the expansion of slavery partly because enslaved labor would compete with and threaten opportunities for free White workers. Thus the best answer is that White men did not have to compete for jobs with enslaved people.

AI-written and checked against the verified answer.