A few days ago I received a letter from Barack Obama, pleading that I “rush a generous contribution” to him. I placed the return envelope in my checkbook.

The same evening I got a call from his campaign asking me to door-knock on the weekend. I already had plans but I agreed to future weekends.

Then I requested a lawn sign. The volunteer informed me that I could buy one at campaign headquarters.

Buy one? Purchased in bulk, a two-color lawn sign might cost the Obama campaign $1. I checked the Obama ’08 Web site. They offer the budget-conscious supporter a generic 26-by-16-inch sign for $8. For those Obamites into conspicuous consumption, the site advertises a variety of 22-by-15-inch designer signs for $19.99. If this were an oil company, the Democrats would be accusing it of price gouging. As Kurt Vonnegut put it, “So it goes.”

I called the Obama ’08 Minnesota office for clarification. Media spokesperson Nick Kimball told me it is “generally a policy of the campaign nationally to charge a nominal fee for lawn signs.” “An occasional exception might be made for an outstanding volunteer,” he added. Kimball later called back to report that “if someone balks at paying for a lawn sign and really wants one, we’ll work something out.”

Gee, I guess I didn’t protest enough.

I contacted Obama’s national headquarters and was told that charging for lawn signs compensates for the income lost when Obama rejected contributions from PACs and lobbyists. Here’s what they failed to mention—any revenue lost from those special interests is more than offset by the cash windfall the campaign is accruing from having opted out of public financing.

What’s wrong with this picture? For a campaign that purports to be a movement, this mercenary marketing strategy is not only hypocritical but also counterproductive. Lawn signs should be an investment, not a revenue stream.

Lawn signs are a biennial ritual for partisans and party activists. Even so, the faithful have minimal influence on their immediate neighbors. However, when a nominal party member or, better yet, an independent puts up a candidate’s sign, the neighborhood takes notice.

Here’s how it works. A couple of households unexpectedly put up an Obama lawn sign. Emboldened by their neighbors, others follow suit. Obama ’08 should be seeking this bandwagon effect: Folks are more likely to put up a sign when they see an increasing proliferation of signs. This effect carries over on Election Day.

So I have learned that even heartfelt allegiances are conditional.

I will write no check nor will I knock on any door until the person answering that door can get a free lawn sign. I urge Obama supporters of conscience to do the same.

I recently spent countless hours writing an op-ed article favorable to Barack Obama. It was a labor of love and a proud contribution to his candidacy. I now realize I was a fool not to have billed my hours to Obama ’08.