Conversation so far:
What job did Elizabeth Blackwell have?
Blackwell began teaching private pupils.
Did she do well?
She worked at intellectual self-improvement: studying art, attending various lectures.
What did that lead to?
she began to articulate thoughts about women's rights in her diaries.
What interesting fact is there regarding her early adulthood?
participated in the Harrison political campaign of 1840.

Question: Why did she participate?
Self-contained rewrite: Why did Elizabeth Blackwell participate in the Harrison political campaign of 1840?