Of all the U.S. Senate seats Republicans hope to win from Democrats in November, there may be few they covet more than that of Barbara Boxer, the powerful California liberal facing a bruising battle with businesswoman Carly Fiorina. But it's not only Republicans who believe that Fiorina, a multimillionaire former Hewlett-Packard CEO, has a chance to knock off Boxer. Political analysts are calling the race a toss-up, and even Boxer's own campaign sees a hard-fought race in the fall. Voter surveys have found that the outspoken Boxer, a strong supporter of President Barack Obama's agenda and a lightning rod for...