Complex sentence: That poll showed only 4.5% of the respondents were against capital punishment in all cases, 79.5% considered capital punishment appropriate punishment for at least some grave crimes and about 10% had difficulty answering these questions or offered no opinion.
Split into simpler sentences: That poll showed only 4.5% of the respondents were against capital punishment in all cases. About 10% had a difficulty answering these questions or offered no opinion.