Anxious Massachusetts Democrats are fretting over finding a candidate to defeat popular new GOP Senator Scott Brown, and some are turning to an intriguing female choice: Victoria Reggie Kennedy, the widow of the former holder of the seat, Ted Kennedy. Vicki, as she’s known, was first urged to campaign for the seat last year and declined, and many say that she would do so again in 2012. Still, party leaders see potential in her, a lawyer, scion of a powerful political clan in Louisiana, and effective advocate on behalf of the health-care legislation that Ted championed his entire life. “Does she have it? Yeah, she’s got it in spades,” said William Delahunt, a prominent Democratic congressman from the state.