Former GOP foe Mitt Romney is the rage in Sen. John McCain's circles as the Republican moves to pick a running mate with good business and economic creds—and moderately youthful good looks. But if you want a really juicy rumor, consider who some key Democrats want for Sen. Barack Obama's No. 2: his veep search aide, Caroline Kennedy. While many Democrats we talked to dissed the idea of a two-minority ticket, others feel it would boost the generational shift Obama represents. And, adds one fan of the idea: "Caroline is the good Kennedy." There's recent precedent. President Bush picked his vice presidential search team leader, Dick Cheney.