CSS issue with the payment option radio buttons

We're using Fundraising on one of our network sites with the Twenty Fifteen theme, and the radio buttons for the Payment Options in the Fundraising pages look really terrible. It's hard to tell which radio button you pick for which option and it's already caused some confusion among our users. How do we space them out more or put them on separate lines so that people can differentiate them better? Thank you. https://anchorgiving.com/ellenreyna/fundraisers/supportme/