Final answer:
Martin Luther King Jr. realized his impact through letters from jail, the March on Washington turnout, and requests to speak at churches.
Explanation:
Martin Luther King Jr. came to realize he was reaching a wide population of people through various means:
- All of the letters he received while in jail reflected the impact of his message on individuals.
- The amount of people who showed up at the March on Washington demonstrated the widespread support for his cause.
- The requests he received to speak at churches indicated his influence on religious institutions.
Learn more about Martin Luther King Jr.'s outreach here:
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