Pickler came into the final "Dancing With the Stars" episode in second place but finished in first.
Fox News reports that the 26-year-old country singer won the show's mirror ball trophy Tuesday.
"This is amazing!" she beamed to her professional partner, Derek Hough.
The pair earned two sets of perfect scores Monday night and another on Tuesday. Judges' scores combined with viewer votes determine the winner.
Because there were problems with voting on the ABC website during Monday's East Coast broadcast, host Tom Bergeron said Tuesday those votes weren't counted. Only votes cast by phone, text and Facebook factored into the final count.
Teen Disney Channel star Zendaya danced perfectly during the final two episodes, collecting the most points from the judges, but she fell short of the title.
"I'm very proud and I'm very happy," the 16-year-old said after the results were read. "And I get to leave here with an amazing experience."
Football pro Jacoby Jones finished in third place. Fellow finalist Alexandra Raisman was axed at the beginning of Tuesday's episode.
"This has been the best experience of my life," the gold medalist said. "My whole life, all I've ever known has been gymnastics, so to try something new has been amazing."
The two-hour finale featured the return of the season's already-eliminated contestants: comedians Andy Dick and D.L. Hugely, Olympian Dorothy Hamill, actor Ingo Rademacher, reality stars Lisa Vanderpump and Sean Lowe, singer Wynonna Judd and boxer Victor Ortiz.
Judd opted to sing rather than dance on the final episode, while Hamill celebrated another chance to hit the ballroom floor.
The Olympic skater, who said she was motivated to join the show after watching fellow skater Kristi Yamaguchi, had to withdraw from the competition early in the season because of an injury.
Hamill danced again Tuesday, and Yamaguchi joined her.
"It's such an honor to join my idol out here on the dance floor," said Yamaguchi, the Season 6 "Dancing" champ.
Korean pop star Psy brought his unique moves to the ballroom by dancing along with his new single, "Gentleman." Pitbull and Jessica Sanchez also performed.
ABC announced earlier this month that the next season of "Dancing With the Stars" will air one night a week instead of two.
