The first appeal was sent to about 1,700 email addresses, all of which has subscribed to the LiveModern News for updates about the site. In essence, the appeal was the text version of the campaign page.

The second appeal was sent about 10 days later to the same list. It was in essence an update on campaign progress (we had been VERY successful, almost doubling our original goal), as well as a friendly reminder for those that has somehow missed our first opportunity to pledge:

Hello again,

As a subscriber to the LiveModern News, I wanted to share with you
the results of our recent appeal to Finally Fix the Forums!

    http://livemodern.com/ploneboard

We had set a 10-day goal of raising pledges from the LiveModern
community of $1,000 toward our overall goal of $2,500.  To date, and
thanks to the generosity of many of you, we have raised $1,820!

We’re well on our way to reaching our overall goal of $2,500.  If
you have pledged, THANK YOU! If you have not yet made your pledge,
please do in the next 3 days so that we can start coding in March.

    http://livemodern.com/ploneboard

I'm asking 35 LiveModern forum users to pledge $20 each in the next
3 days.  We need to get pledges totaling at least $700 to complete
our pledge drive.  Only when all $2,500 is pledged will anyone's
pledge will be automatically converted into an actual contribution.
But don't think that you don't need to pledge first.  Pledge now,
and accelerate the process of fixing the forums.

If you've posted more than a few messages in the LiveModern forums,
you really should pledge your support to this campaign.  Even if
you've never posted, you'll notice the new forum software is much
faster.  $20 is a small price to pay to make sure the conversation
about modernist housing products and services thrives on the net. 
Of course, if you read or post a lot, you can pledge more than your
fair share!

    http://livemodern.com/ploneboard

Please make your pledge in the next 3 days, and we’ll finally fix
the forums!

Marshall

P.S. Your pledge today will be appropriately acknowledged at the end
of the campaign.

P.P.S. You are receiving this email because you have subscribed to
the LiveModern News. Login to change your newsletter preferences.

Two days later, and ever so close to our pledge goal but also right up against the deadline, we sent a third appeal, this time that was published as a News Item but also sent to the original subscriber list of 1,700 members.

These three appeals left us $20 short of our goal as the campaign's public ending date was reached (we had a few days left on the fundable.org campaign). I did some analysis of our forum users and found out that more than 90% of our most frequent posters has not yet pledged! Even though every pledger had received public acknowledgement on the site—a special "contributor" button in their forum posts metadata—the vast majority of the most active forum posters had never made a pledge. Never one to shy away from a challenge, I sent the following appeal the next day to the 77 members that had posted more than 25 times in the LiveModern forums:

Hi there,

I know you are a frequent user of the LiveModern website. You’ve
written at least 25 posts using our creaky forum software. But we
haven’t heard from you in our recent pledge drive to Finally Fix the
Forums!

  * Aren’t you tired of the double posts?

  * Aren’t you tired of the carping about the forum software?

  * Aren’t you tired of the pokiness of the site?

If you are, as I know you are, then here’s your chance to help fix
the forums. You may have ignored this appeal in your email inbox or
on LiveModern (the appeal has been prominently displayed for three
weeks), but now it’s really time to Finally Fix the Forums.

When you contribute, you will be acknowledged along with the 58
other members that pledged $2,480 as of last night. We even had one
member pledge twice, and another pledge $1,000! I even asked by
brother to make the final pledge, but he could not do the whole
amount.

We just need to raise $20 more to start the coding process today.
All funds raised through this pledge drive, even when we exceed our
goal, go directly toward coding, none to LiveModern.

$20, $40, $60—whatever—is a small pledge to make to Finally Fix the
Forums.

Please Pledge Now.

    https://www.fundable.org/groupactions/ploneboard

When you get to the site, it may indicate the at the pledge drive is
"finished," i.e., we’ve reached our goal of $2,500. That should not
dissuade you from making your own pledge. To finally fix the forums,
we’ll likely need a bit more that $2,500 to finish the job.

Marshall

P.S. You may have already pledged, but I won’t know until March 5th
when fundable.org sends me all of the pledge data for this
successful campaign (your email address is partially concealed until
then). So please just let me know if you have already pledged and I
will make sure your forum posts are appropriately acknowledged with
the "contributor" button.

That did the trick. This one appeal rasied over $500 in the final 5 days of the campaign. The end result was $3,040 raised from 79 contributors, and only one person asked to be removed from our list (the result of the first appeal).

You can do it, too. Copy or adapt my text and my methods all you want. And contact me if you need any assistance in the Ploneboard Pledge.

Marshall