Possible Clues:

• Singer Simon
• Singer __ Rae Jepsen
• "Anticipation" singer Simon
• Singer Simon once married to James Taylor
• Simon of pop
• Singer ___ Rae Jepsen
• A rhymin' Simon
• "You're So Vain" singer Simon
• Simon who sang "You're So Vain"
• Rival of Donald, Marco and Jeb