Complex sentence: The Wisconsin primary proved to be the key contest, as Dewey won by a surprisingly wide margin; he took 14 delegates to four for Harold Stassen, while MacArthur won the three remaining delegates.
Split into simpler sentences: The Wisconsin primary proved to be the key contest, as Dewey won by a surprisingly wide margin. He took 14 delegates to four for Harold Stassen, while MacArthur won the three remaining delegates.