Conservatives in Calgary Centre will pick a new candidate Saturday for the upcoming byelection in the riding.

Veteran Tory MP Lee Richardson resigned his seat last May to take a job with Premier Alison Redford.

Six candidates — which include party activists, a former journalist, lawyers, and business people — are vying for the Conservative nomination.

Campaign strategist Stephen Carter says Conservatives are feeling the pressure to pick the right candidate. (CBC)

Richardson won sizeable victories in past elections, but his margins were closer than other Calgary seats and parts of the Calgary Centre riding have voted Liberal provincially.

Conservative campaign strategist Stephen Carter says there's pressure on the Tories to get the right person so they can retain the seat.

“Everybody's taking it for granted,” he said. “You have to recognize that Lee Richardson's a very talented politician. He was able to work with the communities that he represented and he won them over one at a time.”

Political scientist Lori Williams says Conservative members need to be mindful that picking an unpopular candidate could encourage voters to unite behind a more progressive option.

“I think they're thinking it's Calgary — it's a safe Conservative riding — they can get their person to Ottawa if they simply support them, so it's going to come down to who sold memberships more than who the best candidate is, sadly,”

Williams says other parties will also be watching closely who the Tories pick.

“I don't think there's a ton of pressure to retain the seat,” she said. “I think it's relatively safe, but again if the wrong candidate, or a polarizing enough candidate won the nomination, it could leave space in a byelection at least for a combined effort on the part of the NDP and the Liberals.”

Prime Minister Stephen Harper has to call the byelection by the end of the year.

With files from CBC's Scott Dippel