Going by memory - Squeaky Fromme and Sara Jane Moore? A big deal was made of them at the time & I still remember the cover of Time magazine with a picture of Squeaky, all dressed in red.

Can't tell you why it seems to have faded from the public consciousness, though...

Is John Hinkley still remembered?

I don't remember the 1992 attempt on Bush, but at that time I wasn't paying a lot of attention, either... Interesting - couldn't find info on that one via a quick web search, either.