After active involvement in Bingham High School student leadership and extracurricular activities, Ivy began her public political career in 1932 as a delegate to the GOP state convention. Following her marriage in 1935 to Roy F. Priest, a wholesale furniture salesman, she remained active in politics. Even the birth of three children did not deter her. Beginning in 1944 she served for several years as Utah's Republican National Committeewoman and in 1950 ran unsuccessfully against incumbent Congresswoman Reva Beck Bosone. During Eisenhower's campaign for president Priest took charge of the women's division of the Republican National Committee and was credited with the successful drive to get out the women's vote, which totaled 52 percent of Eisenhower's victory margin.

Following her influential work in his campaign, Eisenhower personally called Priest and asked her to take over as treasurer of the United States, succeeding Truman appointee Georgia Neese Clark, the first woman to hold the post. Naturally, she accepted, but in a Deseret News interview she remarked how "overwhelmed" she felt by her appointment and commented "I can't get over the idea of seeing my signature on every United States bill."