First, she made a public commitment via Twitter to help hold herself accountable. This is a tactic that works for many people. Making your intentions know can help you stick to your plans and achieve your goals.
Second, she identified personal reasons for wanting to lose weight. She tweeted that she wanted to feel better, be in better shape, and be healthier. We know that tying your goals to personal beliefs and philosophies can help you stay on track.
Third, she sought to improve her food and movement via help from a personal trainer. Subsequent tweets from the Senator described how she had passed on a funnel cake at the State Fair and how she had given up bread and pasta – actions that would make any paleo proponent proud. So, her diet went from bread and pasta to eggs, fruit, almonds, turkey, fish, and vegetables.
As a result, five months later McCaskill has lost 50 pounds. And, from the looks of her tweets (GOOAALLLLLLLL!! I did it! Lost 50 lbs.), it sounds like she is feeling much better too.