About this Ontario poll from Mainstreet Research
This Ontario poll was fielded by Mainstreet Research in May 2026, with a middle field date of May 6, 2026. The poll collected data from a total sample of n=910 Ontario respondents via IVR technology (automated calls).
The margin of error for an online sample is not applicable.
For comparison purposes, a random sample of this size would yield a margin of error [moe] of ±3.2%, 19 times out of 20 (for entire sample only) around the 50%-mark.
The regional breakdown of this poll was not made publicly available.
If we compare these national numbers with the previous poll from Mainstreet Research (September 2025), the Ontario PC Party loses 13 points from 48% to 35%, the Ontario Liberal Party climbs two points from 29% to 31% (variation smaller than moe), and the Ontario NDP climbs ten points from 14% to 24%.
You can read more information on this poll here.