Possible Clues:

• Malcolm X colleague, informally
• January honoree, briefly
• Jan. holiday figure
• 'I've Been to the Mountaintop' orator, for short
• Reform leader memorialized in the Stone of Hope, for short
• “I have a dream” monogram
• "Injustice anywhere is a threat to justice everywhere" speaker, familiarly
• Stone of Hope likeness, for short
• 'Letter From Birmingham Jail' author, initially
• Leader in the civil rights movement, in brief