Mr Keogh, who resigned as president in August to focus on politics, is also senior associate at Herbert Smith Freehills.
There was a 6.42 per cent swing towards Labor over the weekend, but former SAS army captain Mr Hastie still won comfortably.
The seat was previously held by Liberal member Don Randall, with a margin of almost 12 per cent.
Mr Hastie’s win was bolstered by the change in federal leadership, after Prime Minister Malcolm Turnbull successfully challenged Tony Abbott in a leadership spill last Monday.
Mr Hastie led the two-party preferred vote with 55.4 per cent to 44.6 per cent.
The Canning electorate will be split in the next election, with the new Burt division being created.
The Australian reported that Mr Keogh will be a frontrunner to contest the new seat of Burt at the next election. However, Mr Keogh has not said whether he will run for this seat.