Complex sentence: During the campaign, some Progressive Conservatives spoke of winning "79 in'79", i.e., all seventy nine seats in the legislature, harkening back to Social Credit's unofficial slogan, from the 1963 election, "63 in' 63".
Split into simpler sentences: During the campaign, some Progressive Conservatives spoke of winning "79 in'79", i.e., all 79 seats in the legislature. This harkened back to Social Credit's unofficial slogan from the 1963 election, "63 in' 63".