Moulton, 24, had the high-profile support of Employment Minister Jason Kenney and New Brunswick MP John Williamson.
His rival Paul Smith, a 50-year-old corporate executive, was a former assistant to Mulroney with big-name backers including Mulroney himself, Labour Minister Kellie Leitch and Justice Minister Peter MacKay.
The battle was closely watched in Conservative circles, with some viewing it as a sign of the struggle between the different power and leadership factions inside the party.
Moulton's campaign had been the subject of controversy in the riding and elsewhere in the party ranks, after he sold memberships out of the local Canadian Tire store owned by his father.
The party ultimately approved his candidacy saying no party or electoral rules had been broken.
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