For more than a century, Americans did not vote for their U.S. senators. At the Constitutional Convention of 1787, James Wilson alone argued for popular election and lost 10 to 1, so state legislatures chose senators, a design meant to shield the states from federal overreach and give the Senate a House of Lords style distance from public passions. In practice the system produced long deadlocks and bribery scandals. Indiana left a seat empty for two years in the 1850s, Delaware left one vacant from 1899 to 1903, a third of the Oregon House refused to take their oaths in 1897, and Montana copper baron William A. Clark resigned in 1900 after a Senate committee found he had bought legislators’ votes. Scholars Jay Bybee and Todd Zywicki counter that only ten cases of impropriety were ever formally contested.

The Populists made direct election part of their 1892 Omaha platform, and David Graham Phillips attacked Nelson Aldrich in The Treason of the Senate. The House passed direct election amendments in 1893, 1900, 1904 and 1908, but the Senate blocked them until Oregon’s pledge system and petitions from 31 states for a constitutional convention forced its hand. A 1911 rider would have stripped Congress of power over Senate election rules, protecting Southern disenfranchisement, and it was removed only when Vice President James S. Sherman broke a 44 to 44 tie. The amendment was ratified in April 1913. Today 46 states let governors fill vacancies, and some lawmakers now seek repeal.

• Under the Oregon system, legislative candidates pledged to vote for the winner of a popular Senate primary.
• Senator Joseph L. Bristow of Kansas proposed the amendment that stripped out the race rider.
• By one analysis, the old malapportioned legislatures would have handed Republicans the Senate in 1916.
• Rod Blagojevich was caught on wiretaps trying to sell Barack Obama’s vacated Senate seat in 2009.
• Surveys cited in the episode show about 71 percent of Americans prefer electing senators directly, with 15 to 19 percent backing repeal.