Complex sentence: For the first time television took a prominent role in the campaign, and this was the earliest UK general election of which television coverage survives (the 1950 and 1951 election nights were not recorded).
Split into simpler sentences: For the first time television took a prominent role in the campaign. This was the earliest general election in the United Kingdom of which television coverage survives (the 1950 and 1951 election nights were not recorded).