GARDNER, Kan. (AP) — U.S. Senator Pat Roberts and tea party challenger Milton Wolf have brought their contentious Republican primary race to the Kansas county with the most GOP voters for a parade and door-knocking days before the election. Both candidates participated yesterday (SAT) in the Johnson County Fair's parade in Gardner. Roberts rode in a red truck well ahead of Wolf, who walked beside a campaign bus that has taken him to dozens of stops across the state. Afterward, the two men continued campaigning in the Kansas City suburbs of Johnson County. Roberts is seeking his fourth, six-year term. Wolf is a Leawood radiologist making his first run for public office. At least a few voters remain undecided, and Johnson County is home to more than 20 percent of the state's registered Republicans.