The benefit to Tusk is that his major opponents are out of the picture, giving him a pretty good shot at winning the election which, if he does, is a major benefit to Putin. And you can't dispute the fact that Tusk has benefitted greatly...Kaczynski's party has been annihilated.
Opponent. With 20% approval ratings, Kaczynski wasn't going anywhere but early retirement this summer. Regarding PiS, Jaroslaw has always been the brains behind the the party. However, Lech was definately the more likable, Maria didn't hurt here, and she really came across as an incredibly sympathetic person. I don't know enough about Jaroslaws personal life to comment....no one does.
Anyway, I digress...
For the Senat:
Krystyna Bochenek - PO - deputy speaker
Janina Fetlińska - PiS
Stanisław Zając - PiS
As for members of the Sejm:
Leszek Deptuła - PSL
Wiesław Woda - PSL
Edward Wojtas - PSL
Grzegorz Dolniak - PO
Sebastian Karpiniuk - PO
Arkadiusz Rybicki - PO
Maciej Płażyński - Co-founder of PO, ran on an independent ticket
Grażyna Gęsicka - Leader of the PiS Caucus in the Sejm
Przemysław Gosiewski - PiS
Aleksandra Natalli-Świat - PiS (and all around decent human being, lit a candle at her office)
Krzysztof Putra - PiS, deputy speaker
Zbigniew Wassermann - PiS
Jerzy Szmajdziński - SLD
Jolanta Szymanek-Deresz - SLD
So, the argument that PiS has been annihilated doesn't hold much water.