Your credit card is charged only when the campaign ends successfully, not when you make the pledge. When you pledge to the project, we will send you an email to confirm this, and then when the campaign ends successfully, your card will be charged in that amount. If your card is declined for any reason, you'll receive a notification on how to update your payment details and fix the pledge. This will happen after the campaign is complete.
If the campaign does not reach 80% of it's funding threshold, your card will not be charged.