The extent of this influence isn't yet known but it is doubtful that it completely tipped the scales in favor of one candidate over another. However, the actual engagement in such activities raises a bigger concern over the sovereignty of our election process.
The election process is based on our belief that our votes count and that count determines a winner. If the American people do not have complete trust in the system the fault lines over other issues related to race relations, income disparity, political parties, and socio-economic issues become magnified.
Shockingly, there didn't seem to be a concern by the Russians that such behavior would have a consequence. This would indicate that their national aspirations to rebuild their empire is stronger than their need to be cautious in these situations.
The way to act and react to these situations will become increasingly covert. American intelligence may seek to create their own branded chaos in Russia and the Russians in kind will respond in a Cold War tit for tat that becomes disruptive in a age where almost any computer can be hacked by the right people.
While we find this problem through deep probes into the election process there may be a much wider problem with Senators, Congressman, and even key local officials that have an influence on trade and commerce. It would not be expected that such time and resources would be expended to uncover other issues unless the 13 indicted Russian nationals indicate other campaigns. So while the total impact of this specific situation may be limited it is the potential risk to other elections and the integrity of the process that takes a bite (or better byte) out of the American dream.