This has been studied, famously by Princeton [1]. The chance of any given bill passing is roughly 30% and any amount of public support from 0% to 100% has almost zero impact on that 30%.

Elected offices have become fiefdoms to enrich oneself and maintain the status quo. Anyone who bucks this trend has historically rarely gotten into office or been chased out once they do. This could be from funding another candidate, simply starving an existing candidate of campaign funds or in some cases by redistricting somebody out of a seat.

And look at the reelection rates for Congress [2]. They tend to hover between 90% and 95%.

[1]: https://act.represent.us/sign/problempoll-fba

[2]: https://www.opensecrets.org/elections-overview/reelection-ra...