Opponents heavily outspent supporters of a so-called right-to-work law that was overwhelmingly rejected by Missouri voters in the August primary elections.

New financial reports filed with the Missouri Ethics Commission show that the opposition led by unions spent almost $17 million through a campaign committee called We Are Missouri and through independent expenditures.

By contrast, financial reports show supporters spent less than $5 million through four different committees.

Missouri’s Republican-led Legislature and governor enacted a law last year prohibiting mandatory union fees in workplaces. But labor unions gathered enough petition signatures to suspend its enforcement until a public referendum.

Voters rejected the law by 67 percent of the total vote.

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