There's one scenario that's in fact possible, but would also be very damaging to the DNC itself. Namely, we've all seen e-mails originating from Soros circles claiming that Hillary "is a done deal", indicating that all is being done in such way that Hillary would win, no matter real votes. Or as Stalin once said, it doesn't matter who and how he votes, but he who counts votes matter.
Having so-called "Soros voting machines" installed throuout USA one could imagine that "Hillary is a done deal" may also mean that "Soros machines" were modifed, or in fact programmed (hacked?!) in such way to give desired result. In this case, votes for Hillary.
If what's written above is true than only help to make things right would be either to expose DNC-Hillary-Soros conspiracy (very unlikely, as bought MSM would minimise it and start calling that it's just "conspiracy theory", etc.. Elections would go forward, Hillary would "win" and Trump would be unter tremendeaous pressure to "accept the results") OR to "unhack" said Soros voting machines.
Enters Russians.
If they indeed helped facilitate second scenario, to in fact un-hack Soros voting machines, so that they would calculate election results according to the choice selected by the voter (and not by any other method that would erase voter's will) then it would mean that DNC/Hillary/Obama (and finally CIA) couldn't really say that Russians hacked elections, but rather, they defended US democracy by preventing vote-faud on election day.