The two well-funded candidates, who have torn into one another in broadcast advertisements, differ on what conservatives label a values agenda. Blunt criticized McCaskill for not opposing late-term abortions, although McCaskill said she does oppose them, provided there is an exception for the health of the woman.
Both have been treading carefully on the issue of embryonic stem cell research, which in Missouri cuts different ways. To some, it is seen as a measure of a candidate's views on abortion. To others, notably a Kansas City business community seeking to expand a bio-science sector, it tests a commitment to science and jobs.
McCaskill said last week that she would "veto any bill to criminalize research in this state to save lives," adding that she hoped to prevent it from becoming a wedge issue by educating voters on the difference between "inappropriate cloning" and useful stem cell research.
Blunt said he favors "responsible research." Like McCaskill, he avoided specifics, but he has borrowed a riff from the Bush campaign in castigating his Democratic opponent for failing to share what he describes as Missouri's mainstream values.
"You know," McCaskill said in response, echoing a line familiar to Democrats across the land, "social issues have a place, but we need to make sure that we're fair and not try to be judgmental about each other. These are matters of conscience and we can disagree, but that doesn't mean we should let them divide us."
The race is so close, said David Webber, political science professor at the University of Missouri, that ground troops will play an important part. That, and voters' views of McCaskill's experience advantage and Blunt's ability to surmount it.
"Leadership and competence is probably more important than any issues," Webber said. "I think it's going to come down to turnout in St. Louis and Kansas City versus St. Charles and Springfield."
Did someone mention age and experience?
In her closing statement last week, McCaskill just happened to mention that, "Yes, I'm 51 years old, and Matt Blunt is 33. . . . I've learned an awful lot since I was 33 years old."