John McCain is not talking straight about stem cells in these last days of the campaign. In the last presidential debate he emphatically voiced his support for “stem cell research.” Given that he conveniently left off the word “embryonic” that’s kind of like emphatically supporting the right of Joe the Plumber to hire a publicist.

McCain seems to have studiously avoided that distasteful word for the last few months. So have his emissaries, such as health care advisor Jay Khosla. Here is a video of Khosla at a debate with Obama’s advisor Dora Hughes at Georgetown University last month, which I attended. In response to a direct question, Khosla ties himself in knots and fails to define McCain’s position.

A McCain stem cell ad also avoids the word, and this week his campaign did not clarify its position to the Wisconsin State Journal, which tracks issue because James Thomson, the first researcher to isolate human embryonic stem cells, is at the University of Wisconsin.

There’s nothing controversial about supporting stem cell research. What is controversial is research on stem cells derived from human embryos. Currently, federal funding is banned for embryonic stem cell lines derived after August 9, 2001.

McCain voted twice to reverse the ban. And in September, he told ScienceDebate2008 that he supported federal funding for embryonic stem cell research—although he did not clarify whether he supported expanding funding beyond the few tired and increasingly useless stem cell lines allowed under current policy.

More recently, he’s chosen a running-mate opposed to such research. And he didn’t stop the Republican party from calling, in its new platform, for a “”https://www.medicalnewstoday.com/articles/121088.php">ban on all embryonic stem-cell research, public or private.”

McCain seems to want it both ways. He wants to reassure supporters of embryonic stem cell research, which happen to be the majority of US citizens, that he supports science—while at the same time sending signals to the anti-abortion right wing that he’s on their side.

That strategy seems to have worked. Few scientists or journalists seem to have called McCain on his slippery position, although there are some exceptions. And, judging from a few websites, it looks like the anti-abortion advocates may be feeling more comfortable with McCain’s stem cell positions these days.

Embryonic stem cells offer a more promising source of potential therapies than adult stem cells, which McCain and his advisors prefer to talk about. Obama, in constrast, has been clear on his support for expanding federal funding for embryonic stem cell research.

McCain is counting on the fact that most people don’t really even know what a stem cell is. What he’s probably not counting on is that people don’t like being condescended to.