Complex sentence: Unstated in both is that the marriage of Edward to Edith of Wessex would also support his claim by earning him both the political support of her father Godwin, and an additional connection to Cnut.
Split into simpler sentences: Unstated in both is that the marriage of Edward to Edith of Wessex would also support his claim. Earning him both the political support of her father Godwin, and an additional connection to Cnut.