When Michael J. Fox picked up the phone early last Tuesday morning he was greeted by his mother, in a fury. Two days before, Fox had appeared in a television advertisement for Democratic Missouri Senate candidate Claire McCaskill. Fox, the actor stricken with Parkinson’s disease, was supporting McCaskill and other Democratic candidates because of their support for research on embryonic stem cells. Now Rush Limbaugh, the conservative talk-radio host, was accusing Fox of “exaggerating the effects of the disease” in order to secure sympathy. How could Limbaugh be so cruel, Fox’s mother wanted to know. Fox told her Limbaugh wasn’t getting to him. “I have four kids,” he later told NEWSWEEK. “I have to set an example on how you deal with bullies.”

For a moment last week, Fox and Limbaugh made stem-cell research the premier topic in campaign 2006, no small feat for any issue that isn’t Iraq or a sex scandal. “We wanted to make sure [stem cells] were at the forefront in the campaign,” he says. “That we’re talking about this 11 days before the election is just phenomenal.”

But back in Missouri, Fox’s candidate claimed she hadn’t been following the fracas. Were stem cells one of her top five priorities? “That [is] a mean question to ask!” she replied, indicating she’d rather not say. If she sounded a bit tepid, it’s because no one in Missouri seems to know quite how stem cells are going to play this year. Next week, when voters choose between McCaskill and Jim Talent, the Republican incumbent, they’ll also vote on an amendment to the state’s constitution guaranteeing protection for federally sanctioned stem-cell research. Critics say it creates a legal foundation for the cloning of human embryos and the destruction of innocent life. After Fox’s ad hit the airwaves, opponents of the measure struck back with their own celebrity-filled ad. Most memorable: James Caviezel, the actor who played Jesus in “The Passion of the Christ,” opening the ad in lilting ancient Aramaic. It was a day or so before Caviezel’s words were translated as “You betray the Son of Man with a kiss.” But his intended message was instantly apparent: conservative Christians, come and vote.

If they do, in large numbers, it could spell trouble for McCaskill, who has trailed Talent in recent polls. But Talent himself seems in no rush to step forward as the face of stem-cell foes, mindful that embryonic research splits conservatives–some of whom protest the use of human embryos, while others champion the prospect of cures. (Talent’s campaign did not respond to requests for a comment.)

Missouri is a bellwether: a McCaskill win could push candidates in future races to champion stem cells on the stump. In the meantime Fox is doing plenty of pushing on his own. This week he’ll travel to Iowa, Ohio and Virginia to stump for supporters of the research. The political arena exacerbates his Parkinson’s symptoms, but Fox refuses to slow down. “I’m tired of having my hope qualified as false,” he says. “We’ve reached a point where this can happen now if people get their votes right.”

The Republicans were clearly hoping for a little déjà vu. In 2004, they seized on 11 gay-marriage ballot initiatives to get fired-up conservatives to the polls. Though eight states will vote on similar measures this fall, the issue hasn’t been nearly as electrifying. At least not until last week, when the New Jersey Supreme Court ordered the state legislature to grant gays the same marriage rights as straight couples. Though the court said lawmakers didn’t have to call it “marriage,” the semantics mattered little. “It’s a gift to the White House and the Republican Party if they’re smart enough to use it,” says Gary Bauer, president of the conservative group American Values. President George W. Bush himself extolled the “sacred institution” of heterosexual marriage and complained about “another activist court issue.”

In the past two years, says Family Research Council president Tony Perkins, conservatives have passed gay-marriage bans in 16 states (all but five states now have some kind of ban in place) and won eight court victories. “People were somewhat complacent,” Perkins says, “but this clearly brings the issue of the defense of marriage back into focus.”

With less than two weeks left before the polls close, social conservatives think gay marriage can make a difference again, especially in tight Senate races in Virginia and Tennessee, where marriage amendments are already on the ballot. Bauer says his group may run ads touting the New Jersey ruling in some battleground states.

Gay-rights advocates don’t expect to win many–or maybe any–of the eight ballot initiatives. But, after two years of gay marriage in Massachusetts, they think voters might not be as alarmed about the idea as they were in ‘04. “An angry electorate is looking for real answers on the economy, the war in Iraq,” says Human Rights Campaign president Joe Solmonese. “It’s just not going to resonate this year.” If it does, he says, gay-rights groups will press their case where they’ve had better luck–in court.

The fireworks began before the candidates’ debate even started. Last week Michael Schiavo took a seat only 15 feet away from Colorado Rep. Marilyn Musgrave–all the better to taunt her. She had been an outspoken advocate of what Schiavo considered government intrusion in his wife Terri’s right-to-die case last year. When Musgrave’s camp objected to Schiavo’s presence, one of the event hosts tried, unsuccessfully, to have a cop force him to change seats. Though Musgrave wasn’t asked about Terri during the debate, Schiavo had already met his goal–evoking his wife’s case, and the privacy concerns it raised, for the press and the public. “What you went through is the epitome of what’s wrong with the country,” one man told him afterward.

The issues dominating this election season remain Iraq, terrorism and various scandals, but the Schiavo matter may prove to be a sleeper issue. It has cropped up in contests across the country–from the Florida governor’s race to close congressional campaigns in Connecticut, Pennsylvania and points west. Schiavo himself has helped stoke the debate by campaigning for candidates who backed his position on Terri’s case and lambasting those who opposed him. Using funds raised by TerriPAC, a political committee he founded last year, he has also given 15 candidates a total of $20,000. All of it is aimed at driving home his message: “Government should not interfere with personal matters,” says Schiavo, who still seethes at the memory of Congress’s and President Bush’s attempts to block removal of Terri’s feeding tube.

After mourning Terri’s death, Schiavo had planned to move on with his life (he has a second wife and two kids). But in the course of writing a book about the case, he reviewed news footage that he’d never seen from the height of the controversy. He became incensed all over again–and decided to do something about it, teaming up with Democratic consultant Derek Newton. Schiavo’s hardly an electrifying speaker, and he mangles names on the stump. But he has an ordinary-guy appeal and a wrenching tale. Formerly a Republican, he’s now a Democrat, though he has supported candidates from both parties. As Election Day nears, he’s trying to squeeze in one more round of campaign stops, in response to requests from candidates in Georgia, Iowa and Virginia. And after Nov. 7? “On to 2008,” he says. An activist has been born.

Tiffany Campbell had a serious problem. The ultrasound showed her 15-week-old embryos had twin-to-twin transfusion syndrome, an often fatal complication. Campbell, who lives in South Dakota, was rushed to Cincinnati, where she underwent a procedure that aborted one fetus in order to save the other. On the way home, says Campbell, she and her husband talked about a new South Dakota law that bans all abortions, except to save the life of the mother. “I’m not really for abortion,” says Campbell, 30, still pregnant with the surviving twin. “But then you realize it’s not all black and white.”

Opponents of South Dakota’s abortion ban hope such stories will persuade voters to overturn the law on Election Day next week. Pro-life forces see South Dakota as the beachhead of a new campaign to challenge Roe v. Wade, the 1973 Supreme Court case that established abortion rights. Pro-choice advocates say that defeating the measure will send a signal to the 14 other states considering abortion bans, including cases involving rape and incest, to abandon their efforts.

The law was driven by Leslee Unruh, a Sioux Falls activist who shared with lawmakers her regret over her own abortion. “I bought the feminist line ‘It’s my body’,” said Unruh. Polls show opponents of the ban with a slight lead. Last week the South Dakota Campaign for Healthy Families, a grass-roots organization opposed to the ban, signed up a new volunteer: Tiffany Campbell. “As long as I’m on bed rest, I’ve got plenty of time to stuff envelopes,” she says. For Campbell, a registered Republican, this is her first political campaign.