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Nearly 500 Wisconsin contributors gave a record $4.5 million in 2017 to political nonprofit groups that can raise and spend unlimited cash to influence state and federal elections.

These so-called 527 groups, which are named for the IRS rules that govern them, are run by a host of powerful special interests, like business, health care, manufacturing, energy, transportation, and conservative and liberal ideological concerns. These groups sponsor broadcast ads, mailings, automated phone calls, and other electioneering activities to praise or smear Democratic and Republican candidates at election time.

The Wisconsin contributions to 527 groups in 2017 beat the previous record of nearly $3.5 million in contributions for an odd-numbered year set in 2011. State contributions to these groups in 2015 totaled more than $2.5 million.

The Wisconsin contributions to these groups came from individuals, unions, businesses, trade organizations, tribes, and political committees that state and federal campaign finance laws frequently restrict or prohibit from giving directly to candidates.

Ten Wisconsin contributors gave $100,000 or more and eight of those contributors gave $200,000 or more to 527 groups in 2017. The top contributors were: