Most church stewardship programs that I am familiar with are a waste of time and energy.
I have never seen a campaign that doesn't create a "tax" on the individuals of a congregation, yet churches still continue pushing stewardship campaigns. Statistics also show that a majority of pastors that endure stewardship campaigns often leave that particular congregation within 5 years (although I dispute whether that is completely influenced by stewardship campaigns).
There seems to be a thought that if you keep asking for money, people will keep giving more. I disagree. People want to give more but you have to help equip them in order for them to give.
Help people reduce their personal debt, establish personal saving habits and learn to increase income, and churches will be blessed in the same manner they were a blessing to families of their congregations.
People may give when you speak to their emotions, but they will give more when they can analyze their situation and respond responsibly. Also, I would not assume that only a small part of your congregation is equipped to give significantly. It's probably safer to assume that less than 30% of your members can actually give beyond what they are already giving IF they can even afford what they are already giving in the first place.
If you want people to give more, give to them first.
If you run a stewardship campaign at your congregation, don't do it until you consider Dave Ramsey's Momentum program*. It's not a stewardship campaign and your congregation will be glad you did it.
*Disclaimer: I am affiliated with Dave Ramsey.