South Carolina Superintendent of Education Jim Rex, a Democrat who has squared off against Republican Gov. Mark Sanford over school choice, stimulus funding, and whether the state would participate in the common standards movement, now wants Sanford’s job.

In an opinion piece in The State newspaper, he declared his plans to run as a “turnaround governor” in the 2010 election. Sanford, who famously disappeared for days to Argentina over the summer and ended up admitting an extramarital affair, is term-limited. Rex was elected in 2006 in a tight race that ended in a recount.

When I interviewed Rex in April 2008 for a story on single-gender schools—part of his broader push for more school choice options—I sensed in the interview he had higher ambitions.

And that was confirmed that same day when, in his office, I spotted large postcards he was mailing out to South Carolina residents. In bold letters on the front, was a quote: “South Carolinians expect and demand choices in their lives. They shouldn’t have to make an exception for public education.”

It was signed Jim Rex.

Those campaign-style postcards seemed to be a smart way to start building name recognition throughout the state—a necessary step in any successful bid for governor.