Greg McLean is running for the Conservative nomination in Calgary-Centre. (Greg McLean)

Former Calgary Centre MP Lee Richardson has thrown his support behind financial expert Greg McLean for the inner city seat he left vacant this spring.

Longtime Conservative MP Richardson announced in May he is taking a job as Alberta Premier Alison Redford's principal secretary.

McLean, a venture capitalist, has been a member of the Conservative Party for more than 20 years.

He was the senior policy advisor for the Mulroney government in Ottawa and worked closely with Richardson in the 2011 election.

"Greg will be a very effective voice for Calgary Centre in Parliament," Richardson said in a statement.

The nomination vote for the Tories is scheduled for August 25.

A date for the byelection has not been set.