From some early reports I saw, Brown was actually trying to recreate Jason Kenney's "curry in a hurry" success in reaching out to immigrants and racial minorities, which helped Stephen Harper win from 2006 to 2011. I don't know how successful that would have been in winning the leadership, given that so much of the membership seems to want to focus on the "angry base."
But according to this
National Post article, Brown has a long history at all three levels of government of dodgy allegations:
$1:
Throughout his career as a municipal politician, member of Parliament and Ontario’s provincial legislature and latterly as mayor of Brampton, a Toronto suburb, Brown has had a propensity for attracting accusations of chicanery. Allegations of ballot-stuffing, ethics violations, financial wheeling and dealing, cronyism and high-handedness seem to follow him around like a bad smell. As news of his disqualification broke, a group of Brampton city and regional councillors issued a statement claiming the accusations demonstrate a pattern of behaviour and announced that “a majority group of Brampton Councillors (have) initiated forensic investigations into allegations of financial irregularities, nepotism and possible backroom contract irregularities under Patrick Brown’s failed leadership.”
Links are available at the article itself, which also mentions Brown being accused of sexual harassment. And then there's the fact that
Michelle Rempel Garner, who made the news recently for decrying the venom both federal and Alberta provincial conservatives were throwing at each other, quit as co-chair of Brown's leadership campaign right before his campaign manager left too. Officially, Garner and the campaign manager left to consider a run for the Alberta UCP leadership, but her subsequent statements about the state of the conservative movement make me wonder what other reasons she might have had for quitting Brown's campaign.