What realistic repercussions could Russia face for election hacking?

Question

Written in Russian Cyber Hacks on U.S. Electoral System Far Wider Than Previously Known :

Russia’s cyberattack on the U.S. electoral system before Donald Trump’s election was far more widespread than has been publicly revealed, including incursions into voter databases and software systems in almost twice as many states as previously reported.

[ ... ]

The new details, buttressed by a classified National Security Agency document recently disclosed by the Intercept, show the scope of alleged hacking that federal investigators are scrutinizing as they look into whether Trump campaign officials may have colluded in the efforts. But they also paint a worrisome picture for future elections: The newest portrayal of potentially deep vulnerabilities in the U.S.’s patchwork of voting technologies comes less than a week after former FBI Director James Comey warned Congress that Moscow isn’t done meddling.

What realistic repercussions could Russia face for the reported election hacking, if any at all?

Answer 1

More sanctions.

As this article suggest:

impose new sanctions against Russia for meddling in the U.S. election and its territorial dispute in Crimea.

Sanctions against Russia’s mining, metals and shipping industries would be tied to another bill imposing a new round of penalties against Iran

There is however no publicly available data that proves the Russian government actually "hacked" the election, so these would be hard pressed to justify.