I don't think Putin would attack Poland even if Trump's manages to become the president of the United States again, even if he manages to withdraw from NATO, Poland would still be a member of the European Union and also there will be many countries left within NATO to defend one another against a Russian invasion of Europe. One also needs to keep in mind that an invasion of Poland would imply Putin managed to counter Ukraine or some truce being established between Ukraine and Russia, so the Kremlin could move their forces to Poland.
Without the US, Ukraine would fall within weeks because they would know it would be inevitable. With a Ukrainian victory, a move into Poland would be the logical next step, and without the US involved things get a lot easier for Russia to maneuver. War has thus far been very, very good for Putin, so it's logical that he will continue to engage in it.
Even if Trump manages to win, there could still be a faction within the Republican party which would be pretty much willing to continue to fund the Ukrainian defenders, the President as a centralized authority cannot control all aspects of funding or governing; the Senate and the house of representatives still have pretty much an important influence on the funding of both Israel and Ukraine.
Hopefully, all these conflicts will not longer continue to escalate this year, that would be terrible.
Well, funding for Ukraine is being held up by Trump loyalists right now. It doesn't seem to matter what the majority of Republicans think, only what Trump wants. Trump killed the immigration deal, and he's killed the funding for Ukraine for now. He will be twice as powerful when he's actually president and no Republican in his right mind would go against him.