After the vacancy of the seat held by Senator
James Gordon, the Mississippi legislature convened to fill it. A plurality of legislators (by then all white) then backed the
white supremacist James K. Vardaman, but the fractured remainder sought to thwart his extreme racial policies. A majority united behind Percy to block Vardaman's appointment. In 1910, Percy became the last senator chosen by the Mississippi legislature. That was prior to the adoption of the
Seventeenth Amendment to the
US Constitution for the popular election of senators. Percy held office until 1913. In 1912, he was challenged in the Democratic
primary under the new system by the
populist Vardaman. The campaign was managed by
Theodore Bilbo, who emphasized class tensions and
racial segregation. The tactics caused the defeat of Percy, who was attacked as a representative of the aristocracy of the state and for taking a progressive stance on race relations. He advocated education for Black people and worked to improve race relations by appealing to the planters' sense of
noblesse oblige. The issue of disenfranchisement of Black people caused the Democratic primary to become the deciding competitive race for state and local offices in Mississippi. ==Later career==