Some comments below made me want to look at attitudes toward abortion in the USA by ideology over the decades. I know that political party polarization on social issues has played out mostly over the past 20 years or, but I assumed that this was less evident in ideology (mostly, liberal Republicans became Democrats and conservative Democrats became Republicans). I looked at the ABANY question:
Please tell me whether or not you think it should be possible for a pregnant woman to obtaina legal abortion if:The woman wants it for any reason?
Then I combined years to produce four decades. 1977-1980 = 70s, 1981-1990 = 80s, 1991-2000 = 90s, and 2001-2008 = 00s. I compared this with the POLVIEWS variable, which goes from extremely liberal to extremely conservative. I constrained the sample to whites to control somewhat for population confounds. Below are the results by decade in various formats.
Raw data, % who say “yes” to abortion for any reason:
| Decade | Extreme Liberal | Liberal | Slightly Liberal | Moderate | Slightly Conservative | Conservative | Extremely Conservative |
| 1970s | 62 | 49 | 42 | 34 | 36 | 33 | 31 |
| 1980s | 66 | 56 | 49 | 38 | 38 | 30 | 19 |
| 1990s | 72 | 66 | 59 | 43 | 40 | 26 | 22 |
| 2000s | 79 | 69 | 55 | 42 | 36 | 21 | 26 |
As you can see, the gap between extremes went from 30 points in the 70s to 50 points in the 00s.