But his conception of the president as being above parties, rather than the leader of a party or a coalition, and his style of rule would have made such an effort difficult.

[gleshka]

But his conception of the president as being above parties, rather than the leader of a party or a coalition, and his style of rule would have made such an effort difficult

[mahavishnu]

Предлагаю так:
Но его представление о том, что президент должен быть выше партий, а не лидером партии или коалиции, и его стиль правления, сделали такую попытку затруднительной.