Thaddeus McCotter (R-MI)

LIVONIA, Mich. (AP) -- Congressman Thaddeus McCotter of Michigan plans to donate his leftover campaign money to St. Jude Children's Research Hospital in Memphis, Tenn.

The Republican from the Detroit suburb of Livonia, who dropped his bid for another term earlier this month in a shocking political collapse, made the announcement in a statement Tuesday. Federal records show McCotter had roughly $193,000 in his campaign account as of March 31.

The Michigan attorney general has launched an investigation into why more than 80 percent of the signatures on McCotter's nominating petitions were invalid. The problem developed after the five-term congressman gave up his little-noticed campaign for president and entrusted his staff to prepare his re-election paperwork.

McCotter's district runs from the middle-class communities west of Detroit to wealthy Birmingham in Oakland County.