Both happened.

Let's be very clear about the claim you made.

Committing mass voter fraud

Do you have any evidence of this? If you think evidence is unimportant, you can believe whatever you want, but be honest about it. The most credible allegations I've heard of were about the Democratic primary, regarding discussions between Clinton's campaign and the DNC. There's no evidence of anything more than discussions. Even if there was, calling it "mass voter fraud" would be misleading IMO. Fixing a party election, while morally wrong, is just not nearly as serious as actual fraud in the general election would be. The political parties are not the government, they're private organizations, they can pick their candidate however they want. I think it's misleading to throw around terms like "mass voter fraud" when you aren't alleging actual crimes.

and mishandling classified information

This apparently happened, true.

which allowed foreign countries to get a hold of said information

They would have got a hold of said information anyway. The State Department's official e-mail servers were likewise hacked. In the alternate universe where Clinton didn't keep a private server, Republicans want to prosecute her for not using that extra level of security, like Colin Powell did before her. She violated e-mail security policies but the FBI said it didn't rise to the level of prosecution and no one has alleged any actual harm it caused. If you've got a leaky bucket with two holes in it, it's stupid to blame just one of them.

All in all, I think it remains fair to say that only one of your two scenarios actually happened.