Since the Constitution was changed in 1913 to require the election of senators, a convenient interpretation of the language of the amendment has allowed governors over the years to appoint 188 men and women to the chamber. This undemocratic anomaly has generally gone unnoted, since gubernatorial appointments have rarely threatened to shift more than one state’s seat in the Senate at any particular time. But with the incoming Senate narrowly divided between fifty-one Democrats and forty-nine Republicans, the sudden illness in mid-December of South Dakota Senator Tim Johnson, a Democrat who required emergency brain surgery, focused attention on the fact that one person–in this case, South Dakota’s extremely conservative and partisan Republican governor, Mike Rounds–could make an appointment that would tip the balance of the Senate.

Such a circumstance could never occur in the House, where the Constitution unambiguously requires that open seats be filled by the voters.

Gubernatorial appointees do not always hold on to the Senate seats they are handed, but they go into the next regularly scheduled election with the advantage of incumbency. That means that the practical power of individual governors to influence the long-term makeup of the Senate is often much greater than that of voters.

This is not the way a healthy democracy operates. Two states, Oregon and Alaska, have in recent years changed their laws to join Wisconsin in requiring that open Senate seats be filled by voters in a special election. (Wisconsin, where the Progressives led the fight for direct election of senators, had since the early years of the last century been pioneers in requiring that the choice be that of the voters.) Several other states permit special elections to be called in certain circumstances, but in the vast majority of states it’s the governor’s prerogative. In the absence of a clarification of the Constitution to make it the law of the land that all senators must be elected, state-based activists who seek to reform our political processes from the ground up would be wise to add another demand to their list of steps to address this country’s democracy deficit: No one should sit in the Senate by appointment. Before they take their seats, all senators should first have to face the voters.