While the eos-voter app is still functional, it’s no longer being developed and has been replaced by Anchor.
The error you are getting is because you don’t have enough resources to perform the transaction (resources on EOS are a substitute for fees). Anchor handles all of this for you, where as eos-voter relies on the legacy systems that you need to manage yourself.
You should be able to export your private keys from eos-voter and then import them into Anchor. Depending on what version of eos-voter you have, you may need to upgrade to enable that option. eos-voter version 0.7.12 was the last version, which has the export feature under the Manage Accounts/Wallets section, and in the right column of each account there’s a “View Details” option that allows you to see the key being used for the account in the wallet and export it.
If you need to upgrade, here is the download page for eos-voter 0.7.12:
You can just install the app again with the appropriate installer and it’ll perform the upgrade.
Once you have that private key, you can import it into any compatible wallet, of which I’d recommend Anchor since it’ll deal with all the resources headaches for you and allow you to connect with sites like bloks.
You can find the latest version of Anchor here: