Possible Clues:

• Boring type of car – those who have one are certain to stay in the house
• Good place to stand, protected from swings?
• Peterhouse represented at Westminster?
• Equestrian ability acquired by large majority
• One stands to win this easily
• Peter's country mansion, one of a great majority
• See a fast scramble to be an MP's banker
• Constituency unlikely to be lost
• One'll return as expected, perched holding iron drink
• Equestrian ability acquired by the large majority