Let's be clear about one thing: No political candidate ever says anything out of the goodness of his heart. He says everything out of the badness of his heart in the fervent hope that the effect of whatever he says will accrue to his own personal benefit.

In the catalog of known truths, that one leads the table of contents. Such that when Sens. John Edwards and John Kerry began waxing poetic about the gay daughter of Vice President and Mrs. Dick Cheney in response to campaign questions about homosexuality and same-sex marriage, they were not being nice.

They were being political. Deliberately, studiously and condemnably.

Non-political folk - the "ordinary people" of whom politicians are so seasonally fond - know this instinctively and are justifiably incensed that the Democratic presidential nominee and running mate have used a family member, innocent by virtue of the genetic accident called birth, for political gain.

Mary Cheney, the lesbian daughter of Dick and Lynne Cheney and involuntary pawn in this classless political season, is not running for public office last time we checked. Yet her name has been injected twice into the political whirlwind - once when Edwards and Cheney debated, and again during the third and final debate between President George W. Bush and Kerry.

In both instances, the moderator posed a question about the candidates' positions on same-sex marriage, and both times the Democratic candidates were compelled to mention Mary Cheney. Following criticism and some angry remarks by the Cheneys, both Kerry and Edwards have pleaded acute empathy and said they hoped only to do some good in being open and demonstrating tolerance.

Whereupon we note with regret that only Barnum & Bailey have shovels equal to such moments. Piffle. In either instance, Kerry and Edwards could have offered their thoughts on the constitutional question without naming the Cheneys' daughter.

It is true that the idea, if not the name, of Mary Cheney was suggested by the moderator in the vice presidential debate. When PBS's Gwen Ifill directed her question to the vice president, she reminded Cheney of his having once said, "Freedom means freedom for everybody," noting that Cheney used his family's experience as a context for his remarks.

She then asked Cheney to describe the Bush administration's support for a constitutional ban on same-sex unions. At no time in the debate did Cheney mention his daughter, though Edwards did - in the nicest possible way, as Southerners say when someone backstabs them with a smile and a nice squash casserole.

Worse, Edwards more or less congratulated the Cheneys for loving their gay daughter, as though it were a sacrifice deserving of commendation. And though Cheney graciously thanked Edwards for "the kind words he said about my family and our daughter," many in TV land heard Edwards' remarks as condescending and inappropriate.

How much better had Edwards said instead: "I'd rather not bring the Cheney family into this debate, so let me address my comments to the principle." Or some such. Continued...