Final answer:
The number of credits needed to update voter registration varies by state and should be checked to ensure eligibility to vote.
Step-by-step explanation:
When it comes to updating your voter registration, the number of credits you need every two years can vary depending on the state you live in. In some states, you may not need any credits at all, while others may require you to complete a certain number of credit hours. For example, in California, you can update your voter registration through the Department of Motor Vehicles. It's important to check the specific requirements of your state's electoral system to ensure that you stay registered and eligible to vote.