From Noah's March 4 Slate post titled, “Why Stupak is Wrong”:

Stupak is right that anyone who enrolls through the exchange in a health plan that covers abortions must pay a nominal sum (defined on Page 125 of the bill as not less than "$1 per enrollee, per month") into the specially segregated abortion fund. But Stupak is wrong to say this applies to “every enrollee.” If an enrollee objects morally to spending one un-government-subsidized dollar to cover abortion, then he or she can simply choose a different health plan offered through the exchange, one that doesn't cover abortions. (Under the Senate bill, every insurance exchange must offer at least one abortion-free health plan.)

One dollar exceeds health insurers' actual cost in providing abortion coverage. In fact, it's entirely symbolic. The law stipulates that in calculating abortions' cost, insurers may consider how much they spend to finance abortions but not how much they save in foregone prenatal care, delivery, or postnatal care. (This is on Pages 2074-2075.) This is to keep insurers from pondering the gruesome reality-one they surely know already-that covering abortions actually saves them money. For health insurers, the true cost of abortion coverage is less than zero, because hospitals and doctors charge less to perform abortions than they do to tend pregnant women before, during, and after childbirth. (Ironically, only the Senate bill-not the House bill-provides some small counterweight to this calculus by increasing aid for adoption assistance.)

What really rankles Stupak (and the bishops) isn't that the Senate bill commits taxpayer dollars to funding abortion. Rather, it's that the Senate bill commits taxpayer dollars to people who buy private insurance policies that happen to cover abortion at nominal cost to the purchaser (even the poorest of the poor can spare $1 a month) and no cost at all to the insurer. Stupak and the bishops don't have a beef with government spending. They have a beef with market economics.