ST. PAUL, Minn. (AP) — A Michigan philanthropist has donated $325,000 to a group opposing a proposed constitutional ban on gay marriage in Minnesota.

Jon Stryker of Kalamazoo, Mich., gave the money to Freedom to Marry Minnesota’s political action committee on Tuesday, according to state campaign finance records.

The contribution comes a day after the Washington-based Human Rights Campaign pledged to sink $1 million into four states where voters will consider gay marriage ballot measures. The group is donating $250,000 to Minnesota opponents of the gay marriage ban.

Freedom to Marry is a coalition partner of Minnesotans United for All Families, the main organization working to defeat the constitutional gay marriage prohibition.

Stryker is heir to a medical products company fortune.

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