Can I upgrade my kickstarter donation?

I donated $20 on the 2nd day. Can I now pay another $20 to get to the $40 reward level? Or do I need to give $40 (total of $60)??

Thanks!

You can just add 20 you will get an email/survey at the end in which you can state which type of reward you want

in your case you would be able to choose:

-1 beta key
or
-2 normal keys

Great, thanks

You can manage your pledge, It's the big green button. You can change your pledge amount and reward level until the kickstarter closes.

That depends on whether he used kickstarter or PayPal on the site.
I used Paypal, but use the green button with Kickstarter I guess.