Feb. 2019: Pro-Whitmer group broke Michigan campaign finance laws, Benson finds​

Oct. 2018: Truth Squad | Ads unfairly attack Whitmer on healthcare, missed votes

Sept. 2018: Turning Gretchen Whitmer into Granholm, a Republican gamble in governor race

August 2018 update: Gretchen Whitmer wins Democratic primary for Michigan governor

Related: Get to know Garlin Gilchrist II, Gretchen Whitmer's pick for Lt. Governor

Facing accusations that it was hiding donors until after the Aug. 7 gubernatorial primary, a political group tied to Democrat Gretchen Whitmer on Monday released the identity of those who donated more than $2.23 million to the group.

The list includes nearly $2 million from union groups, affiliates and progressive organizations, more than $150,000 from individuals and nearly $90,000 from businesses.

Build a Better Michigan - running $1.8 million in campaign ads that feature Whitmer, a former state senator - was required to file its financial disclosure report with the Internal Revenue Service on July 15. But it did so by mail, while IRS officials said it would take weeks to upload the report and make it public.

That sparked accusations last week from a progressive Whitmer rival, Abdul El-Sayed, that Whitmer was benefiting from what he called a “dark money group” whose lack of disclosure he said is “corrupting our Democratic primary.”