Why is presidential hopeful Kamala Harris lagging in polls?

California Democratic Senator and 2020 presidential hopeful Kamala Harris unveiled a sweeping criminal justice reform plan today. She wants to end the war on drugs, the death penalty and solitary confinement, and mass incarceration. She wants to phase out for-profit prisons. And she wants to legalize pot. 

Harris has acknowledged that the plan is more progressive than her record as a prosecutor and as California’s attorney general.

But will the plan light a fire under her bid for the White House? In the polls, she's behind top-tier candidates like Joe Biden, Bernie Sanders, and Elizabeth Warren.