Complex sentence: Campbell initially tried to form an alliance with the CCF (Stinson would have served as Minister of Welfare), but these plans came to nothing and the CCF allowed the Tories under Dufferin Roblin to form government.
Split into simpler sentences: Campbell initially tried to form an alliance with the CCF (Stinson would have served as Minister of Welfare), but these plans came to nothing. The CCF allowed the Tories under Dufferin Roblin to form government.