True

https://www.researchgate.net/publication/341609819_Mental_Illness_and_the_Left

Emphasis on this graph. Farthest left has a self reported mental illness of 32%. Farthest right is 11.8%.

https://www.researchgate.net/figure/Self-reported-mental-health-and-self-reported-political-label-Reproduced-from-Lemoine_fig1_341609819

True

https://www.researchgate.net/publication/341609819_Mental_Illness_and_the_Left