A man who was once the top Republican in the Iowa Legislature, and a major backer of Senator Charles Grassley’s career has died. Delwyn Stromer died Sunday at a Des Moines hospital. He was 73. Stromer was first elected to the Iowa House in 1966, serving the area in north central around Garner, which was his home. Stromer retired from the legislature in 1989, and he later served as an aide to Senator Charles Grassley. The two men had served in the Legislature together in the 1960s. Stromer is the lawmaker who gets chief credit for devising the formula that has distributed state aid to schools since the 1970s. Stromer’s daughter, Linda Upmeyer of Garner, was elected to the Iowa House last year.