1. Lovejoy Incident: In 1837, during Lincoln's time as an Illinois state legislator, he faced criticism for supporting Elijah Lovejoy, an abolitionist publisher. After Lovejoy's press was destroyed and he was killed by a pro-slavery mob, Lincoln's position opposing the press' destruction and advocating for freedom of speech was controversial. Some political opponents used this situation to attack his stance on slavery and free speech.
2. New Almaden Mine Controversy: Later in 1847, when serving as a Whig congressman from Illinois, Lincoln found himself embroiled in the acquisition of mining rights related to the New Almaden quicksilver (mercury) mine in California. His connections with William E. Talcott, who had claimed possession of the mine but faced a competing title claim backed by influential investors in Washington, led to allegations of a conspiracy to secure exclusive federal control of mine exploitation. This episode tarnished Lincoln's reputation and resulted in the loss of his congressional seat two years later. These controversies contributed to some criticism and attacks, but their exact impact on Lincoln's future presidential campaigns or long-term reputation is challenging to quantify precisely.