According to OpenSecrets, Sheet Metal Workers Union was the United States' 27th largest donor to federal political campaigns and committees, having contributed over $51.8 million since 1989, over 90% of which went to the Democratic Party and other liberal groups.
Sheet Metal Workers Union ranked as the US's 27th biggest donor to federal elections, with contributions totaling over $51.8 million between 1989 and now, approximately 90% of which have gone to the Democratic Party and left-leaning groups.