Customers may list their eNewsletters on their payment page so their patrons can opt-in during the check out process. When patrons opt-in their contact information is automatically sent to their MailChimp account.
Click & Pledge offer a discount for MailChimp customers:
$50 off our application fee (application fee for the payment system is $150) 0.25% discount off our published transaction fees For standard account customers, our advertised transaction fee is 4.5% so your customers’ rate will be 4.25%. For premium accounts, rates begin at 3.95% so they would reduce to 3.7%. To receive this discount, please use this link: https://apply.clickandpledge.com/default.aspx?PID=92
Click & Pledge has worked with nonprofits and similar organizations since 2002 and currently they have over 9,000 customers in 46 countries.