The General Social Survey asks whether the respondent favors or opposes the death penalty for persons convicted of murder.  The interactive visualization below reports the % who favor the death penalty.

Some interesting cross-sectional differences and longitudinal patterns to note: 

Support for the death penalty was generally low in the mid-70s, before climbing to peak levels during the Reagan/Bush era.  Across all groups, support for the death penalty has decreased since then, returning to approximately the same levels observed in the 70s.  

When we segment by ideology, religiosity, and socioeconomics – there is a clear pattern of increasing then decreasing support for the death penalty. The exception to this are those who identify as Republicans,  among whom support for the death penalty remains high.

 Across groups we find large differences in support based on race and ideology, with higher levels of support amongst whites and conservatives. 

Data can be found and downloaded here.