There is no hiding the frustration singer Nancy Sinatra feels in Sen. Hillary Clinton's loss in the presidential primaries to Sen. Barack Obama. "I was disappointed in the Democratic result, and now I don't know what I'm doing," says the star known for hits like "These Boots Are Made for Walkin.' " "I know it's one vote and it's not a big deal in the scheme of things, but to me it's very important," she adds. Sinatra, in Washington to promote legislation requiring radio to pay royalties to performers, says the nation needs a woman as president. And like many Clinton backers, she's on the fence between Obama and switching to Republican Sen. John McCain. "I'm listening, and I'm watching, and I'm learning," she says, though "anything that smacks of the current administration is not going to be my thing." But a warning to the Obama campaign: She doesn't see Mac as Bush III. "I don't necessarily believe that's true," she says.