there are a lot of variables to consider, and ideology is just one. but if we look at how some of the other texas candidates most similar to cisneros in ideology fared:
tx 10 (siegel): 45.4-52.5, biden 48.3-50.0; underperformed biden by 5.4
tx 24 (valenzuela): 47.5-48.8, biden 51.9-46.5; underperformed biden by 6.7
tx 25 (oliver): 42.1-55.9, biden 44.4-53.9; underperformed biden by 4.3
tx 31 (imam): 44.3-53.5, biden 47.5-50.4; underperformed biden by 6.3