Related Clues:

• Promotion
• Alamo event
• Persistent attack
• WWII Leningrad event
• Prolonged assault
• Attack from all directions
• It may force a city to surrender
• Seek votes
• Campaign against Troy, e.g.
• Encircling tactic
• Hit the trail, in a way
• Attack tactic
• Long period, as of illness
• The Trojan Horse ended one
• Battle of attrition