one has to define win. as in collapse of the west? The USA splits up?! that's a tough sell.
outside of the moon, the soviets won the space race for all intensive purposes they hold most firsts.
the soviets excelled in sports and cultural things such as music and ballet along with education and science.
The soviet collapse could very much have been prevented, that said the repression needed to keep it going would be quite ugly and unproductive from a population stand point.
The Soviet Union Reforms, opens up and becomes more liberal ( not full on USA crazy, but more of a Social-democratic-semi free market federation ? Baltics go their way. plausible. would require a lot of political skill and moxie to keep things together but its not impossible.
Khrushchev was the key time for this to happen. to disavow stalins policies, to work to build a more fair and equal soviet society. ( we saw what that got Khrushchev.
Brezhnev kicking the bucket mid 70's might help, Andropov while still old school understood that things needed to change, does he act on it? It took Gorbachev and the younger generation to finally push to undo Stalins system, once that can of worms was open ( much to late ) everything blew apart. Combine that with Distrust of the Soviet Government by its own people, the growing disparity between east and west, long lines, fluctuating policies from Moscow on glasnost and perestroika, Chernobyl; ( they waited 3 days to tell people and evacuate!, over may 1st celebrations! )
The Soviet Union was not going to "WIN" the cold war. Adapt, and thaw, yes. outright win? no, and hell to the astonishment of the United States and everyone else, NO ONE expected the Soviet Union to collapse as it did.
the old saying applies, if the foundations are rotten and no one is fixing it, well.. you get what you invest in.