Being a fundraiser I've learned a few things:

1.  Don't be embarrassed to ask anyone.  You are not asking for money for you or your race, you are asking to support the cause.  Ask multiple times.  Put your website out in emails and on social media every week or so.  Make sure everyone sees your message.  A month before the race, flood everyone with news, making sure they know the race is soon. 

2.  Don't assume someone won't give.  Ask anyway.  His dad could be a Veteran, so the cause could hit close to home. 

3.  Take whatever people can give.  Some people are embarrassed because they don't have much.  Last race, I had a girl I who is down on her luck stop by with a $10 bill.  That $10 meant more to her than most of the $100 and $200 donations I've gotten, but she helped the cause.

4.  Have your website on you at all times.  I have business cards made with my website on it.  They cost like 5 bucks for 500 cards, but when you're in the bar and talking about the race and someone says they're interested in donating, hand them the card, it's much better than, "I'll get you the info soon".  You'll forget to pass the info.

5.  Think out of the box.  I live on the corner of a cross street where runners, bikers, and dog walkers pass.  I had a banner made saying I was running the race for SFF, take a card.  The number of complete strangers that donate is amazing.

6.  Get the cause out there.  Wear your SFF shirt at every race.  People ask what it is.  Tell everyone that your running and why.

I could raise $400 in my sleep, $400 should be your minimum, not your goal.