Scarborough-Sud-Ouest
Provincial by-election in Ontario on September 3, 2026, after the departure of Doly Begum (Ontario NDP).
The NDP is the favourite, with a 79% chance of winning and 42% of the projected vote.
Results
Connecting to the official count…
Preliminary results · Elections Ontario
The forecast
| Party | Projected share | Range (80%) | Chance of winning |
|---|---|---|---|
| Fatima Shaban Ontario NDP | 42.0% | | 79% |
| Ahsanul Hafiz Ontario Liberal | 27.1% | | 15% |
| Noor Tarun Progressive Conservative | 27.1% | | 6% |
| Mark Bekkering Ontario Green | 2.7% | | <1% |
| Other | 1.1% | | <1% |
Only two points are stripped: her first election produced the smallest New Democrat premium on record, which is hard to read as a personal effect. One risk is deliberately left unmodelled — Begum did not merely leave, she joined the Liberals and won under their banner. Some of her personal following may follow that move to the Liberal candidate, but nothing in the record lets us size that yet.
The local poll
The published figures include 22% undecided. With no breakdown released, we split them in proportion to stated intentions.
The poll carries about <1% of the riding’s starting point, before the simulations run. That weight rises with each new poll, according to its size and date.
One firm, one wave. Sample size, margin of error and method were not published, so we treat it with wide uncertainty.
What the forecast adjusts
- Personal vote removed
- 2 points removed from the Ontario NDP vote: the share that went to Doly Begum rather than to the party. 44.2% → 42.2%
The 2025 result
The race
Doly Begum resigned in February 2026 to run federally — for the Liberals — and won in April. It is tempting to read the New Democrat share here as hers. The record says otherwise: the seat ran more than 22 points ahead of the provincial NDP before she was ever on the ballot.
- Begum, NDP MPP since 2018, stepped down in February 2026 to run for the Liberals in the federal Scarborough—Southwest by-election, which she won on April 13, 2026 with 69.6%.
- New Democrat share versus their province-wide score: +22.0 points (2011) and +23.0 (2014) — years before she was elected.
- Under Begum: +12.1 (2018, her first election and the LOWEST premium on record), +23.9 (2022), +24.4 (2025).
- Four candidates are named: Dr. Noor Tarun (PC), Ahsanul Hafiz (Liberal), Fatima Shaban (NDP) and Mark Bekkering (Green).