Most Americans just look what’s on the news then get on with their day. The technical majority of public opinion alone doesn’t translate into political power when most people are generally apathetic beyond some performative politics to inject some engagement into their socially-starved lives.
In fact, it being only 70% (or even 80%) is likely a cause of concern for the state which used to enjoy near-unanimous support from the electorate in this issue in particular and calling Israel an apartheid state was something only kooks would say. Especially when pro-Palestinian and pro-ceasefire demonstrations have been met with state violence almost immediately (and so far look to be growing as the media consensus is cracking).