It's a two-person battle between deputy PC leader Christine Elliott, the widow of former finance minister Jim Flaherty, and Barrie MP Patrick Brown, a federal Conservative backbencher.
Every party member is eligible to vote, and the 36-year-old Brown claims he's leading the race because he sold more than 41,000 PC memberships.
However, the 60-year-old Elliott, who claims to have sold 34,000 memberships, says Brown's support is concentrated in a small number of ridings and is not nearly as widespread as hers.
Each of the 107 ridings gets 100 points for the new leader, so having support all across Ontario is just as important as how many memberships were sold.
Elliott, who was third in the PC's 2009 leadership race, says Brown's views are outside the Ontario mainstream, while he calls her "Liberal-lite" and insists she represents the "same old same old" from the Tory establishment.
Most PC caucus rallied behind Elliott earlier this week when former leadership candidate Monte McNaughton — a Brown supporter — attacked her as a more of a 'Trudeau Liberal' than a real conservative.
But interim Conservative Leader Jim Wilson said emotions always run high in the final week of a leadership campaign.
"It's not as bad as it could have been," Wilson said with a laugh.
Former Progressive Conservative leader Tim Hudak resigned shortly after the Tories lost their fourth consecutive election to the Liberals last June, the second under his leadership.
Both candidates spent the leadership race criticizing Hudak's 2014 campaign pledge to cut 100,000 public sector jobs — although Brown pointed out that unlike Elliott, he has no baggage from the provincial campaign.
At one point Elliott called Brown "an untested candidate with nothing more to offer than a life lived as a career politician'' who "has done little of significance and has no substantive record.''
Brown, who was elected to city council at age 22 and then to Parliament at age 27, said Elliott is the establishment candidate and is supported by the backroom strategists and party brass that lost four elections.
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