Final answer:
Union victories, such as the fall of Atlanta and General Philip Sheridan's successes in the Shenandoah Valley, helped Lincoln win reelection.
Step-by-step explanation:
Union victories, including the fall of Atlanta in September and General Philip Sheridan's successes in the Shenandoah Valley of Virginia, provided the victory needed to help Lincoln win reelection. These victories bolstered Lincoln's popularity and his reelection bid. He won almost two-thirds (64 percent) of the 1,118 counties in the 25 states where popular voting occurred, and even Union army troops voted overwhelmingly for him.