Jimmy as a pollster searching for the perfect, average American town in MAGIC TOWN (1947) which also featured Jane Wyman.
Jimmy began to break out of his somewhat stereotypical Capra-esque roles after he returned from serving in World War II. Above is a poster from CALL NORTHSIDE 777 (1948) in which Jimmy plays a reporter, convinced that a man convicted of murder is really innocent, who sets out to prove it.
In 1950, Jimmy was nominated for Best Actor for his portrayal of Elwood P. Dowd, a simpleton whose best friend is an invisible six-foot rabbit named Harvey. Elwood's family believes he's crazy, but somehow no one can quite seem to pin point the problem. Even notable psychiatrists like Dr. Chumley (Cecil Kellaway) find themselves playing patient to Elwood's kind and compassionate persona in HARVEY (1950).
A poster from MR. HOBBS TAKES A VACATION (1962) with Maureen O'Hara. Jimmy takes on the father and even grandfather figure role, but family vacations aren't quite like they used to be.