This process worked without major problems through the mid-1850s, when the American Civil War was in the offing. Because of increasing partisanship and strife, many state legislatures failed to elect Senators for prolonged periods. For example, in Indiana the conflict between Democrats in the southern half of the state and the emerging Republican Party in the northern half prevented a Senate election for two years. The aforementioned partisanship led to contentious battles in the legislatures, as the struggle to elect Senators reflected the increasing regional tensions in the lead up to the Civil War.
After the Civil War, the problems multiplied. In one case in the mid-1860s, the election of Senator John P. Stockton from New Jersey was contested on the grounds that he had been elected by a plurality rather than a majority in the state legislature.[1] Stockton defended himself on the grounds that the exact method for elections was murky and varied from state to state. To keep this from happening again, Congress passed a law in 1866 regulating how and when Senators were to be elected from each state. This was the first change in the process of senatorial elections. While the law helped, there were still deadlocks in some legislatures and accusations of bribery, corruption, and suspicious dealings in some elections. Nine bribery cases were brought before the Senate between 1866 and 1906, and 45 deadlocks occurred in 20 states between 1891 and 1905, resulting in numerous delays in seating Senators. Beginning in 1899, Delaware did not send a senator to Washington for four years.
And beyond that, you had to convince most of the state legislatures to give up power. That doesn't happen on a whim.
