The Harmony party has reclaimed the top spot with 19.2% – down 0.7% from May – as the Union of Greens and Farmers lost first place and is now at 17.1% – down 3.2% from May.
The National Alliance would receive 7.8% (down 1.4%) of the vote, while Unity would get 5.4% (unchanged).
Two parties currently in the Saeima - Latvia from the Heart (3.1%) and the Regional Alliance (2.3%) - would not receive the required 5% of votes to make it into parliament.
Latvia's ruling coalition consists of the Greens, National Alliance, and Unity.
The results come from an opinion poll that the SKDS pollster carried out for Latvian Television.
Arnis Kaktiņš, head of SKDS, told LTV that the Greens might have lost some of their popularity as former Health Minister Guntis Belēvičs resigned after being caught jumping in line for a minor surgery.
Kaktiņš, together with Juris Rozenvalds, dean at the Faculty of Social Sciences at the University of Latvia, agreed that KPV's performance reflects the common tendency in Europe, where growing numbers of people are unhappy with the ruling elite, and they are not demanding as concerns the alternatives.