Thomas Andrews Hendricks—nicknamed "The Professional Candidate" by allies and enemies alike—became the 21st vice president of the United States after a lifetime of loyal service to the Democratic Party.

He was born on September 7, 1819, near Zanesville, Ohio. As a young boy, he moved with his family to Indiana, where his uncle was the soon-to-be governor of the state. Thomas was raised as a Presbyterian and a Jacksonian Democrat. He graduated from Hanover College in 1841 and was admitted to the Indiana bar two years later. In 1845, he married Eliza Morgan, and they had one son who died as a young child.

Hendricks's political career began with his election to the Indiana House of Representatives in 1848, and he was elected to the U.S. House of Representatives in 1850. In Washington, D.C., he was allied with Stephen Douglas of Illinois and supported the Kansas-Nebraska Act, which repealed the Missouri Compromise of 1820 and allowed the residents of the territories to determine whether or not they wanted to permit slavery. He was defeated for reelection in 1854. President Franklin Pierce then asked him to be the commissioner of the General Land Office in the Interior Department. As commissioner, Hendricks was considered efficient and able; he left the office after James Buchanan became President. In 1863, the Indiana state legislature elected him to the U.S. Senate, where he served until 1869. Arriving in the midst of the Civil War, Hendricks led the few remaining Democrats in the Senate; many were Southerners who had left the federal government. He supported the Union and the war effort but was critical of Lincoln's leadership. He also did not believe in equal rights for blacks and did not support giving them the right to vote. After the war, Hendricks was an opponent of Radical Reconstruction, favoring President Andrew Johnson's policies of quickly reintegrating the South into the Union and not protecting the rights of the newly freed slaves. He did not vote for the Fourteenth Amendment (citing the absence of southern representation in Congress) and actively opposed the Fifteenth Amendment (which gave freed male slaves the right to vote).After he lost a race for governor of Indiana in 1868, he returned to private law practice. In 1872, he ran again for governor and won. During his tenure as governor, he became associated with agrarian reform and "soft money," which did not favor backing paper currency with gold. In 1876, the Democrats chose Hendricks to be vice president on the ticket with Samuel Tilden. After the close election, the electoral college of three southern states was still undecided. Congress put together a special electoral commission to decide the election, and the commission ruled in favor of the Republicans, making Rutherford B. Hayes President. Although the Democrats felt they had been robbed, Tilden and Hendricks chose to accept the commission's ruling rather than risk further civil strife in the country. Hendricks returned to his law practice and gave many public speeches. In 1884, the Democrats again turned to Hendricks as the vice presidential candidate. In part they chose him to balance the ticket with Grover Cleveland, a hard money man from New York, but there was also a sense that Hendricks had lost out after the 1876 election. He worked hard campaigning, and the Cleveland-Hendricks ticket won the election. As vice president, Hendricks was interested in using his position to reward his supporters with patronage. However, Cleveland was one of the first Presidents to support civil service reform and disagreed with his vice president on using patronage. After suffering his first stroke in the early 1880s, Hendricks's health gradually declined. He died on November 25, 1885, at his home. In response to his death, Cleveland called for a new line of succession resulting in the Presidential Succession Act, which changed previous legislation by placing in line for the presidency, after the vice president, the heads of each executive department in the order in which the department was created. The new system provided a long list of successors, making it all but impossible for the nation to be without a chief executive. It remained in effect until 1947.