While television cameras loom over him, Edward Kennedy hunkers down with the tots in a day-care center run by a labor union. Reading a nursery tale -- it is more gripping stuff than his staff writes for him, and he reads it well -- he pauses, by senatorial reflex, to grill his listeners: "Should the bunnies play with the fox?" "Do you play 'Duck, Duck, Goose'?"

Kennedy is here to energize Adlai E. Stevenson III's campaign for governor. The Republican incumbent, seeking an unprecedented third term, is Big Jim Thompson.

Thompson's middle name is, evidently, Jim. When his parents carried him in diapers to the baptismal font, and the minister asked what name he would have, the answer seems to have been: "Big."

Thompson (6-feet-6), a former prosecutor, has a campaign style that stops -- usually --just short of being overbearing. Stevenson's style is called "professorial," a slander the teaching profession can do without. Because Stevenson tends to fade into the wallpaper, Kennedy came to attract cameras and lead the tots in singing "Solidarity Forever."

The "wimp" motif has received more than its fair share of attention since Stevenson complained that Thompson thought that he, Stevenson, is one. But personalities are apt to be the focus of attention when there is little confidence that anyone's policies will make more than a marginal difference.

Besides, Illinois bears little resemblance to Pericles' Athens. Illinois is a sprawling, and frequently brawling, kingdom. Its north is farther north than Cape Cod and its south is farther south than Richmond, and its legislature sometimes suggests scenes cut, in the name of taste, from the movie "Animal House." It takes a strong personality to prevent this state's centrifugal forces from obliterating all consensus about the collective good.

Stevenson is a good argument for a House of Lords. If appointed Lord Adlai of Libertyville, he could bring his thoughtfulness and public-spiritedness to bear without campaigning. As a campaigner, he resembles the lilies of the field: he lacks pep. When it comes to drinking raspberry schnapps out of a toilet plunger, Stevenson is a dead loss. Stevenson, shuddering, says Thompson did that. Thompson's staff hotly denies it. Pericles, call your office.

Here, as in New York's and California's gubernatorial contests, recession has concentrated minds on competitive possibilities inherent in federalism. There is nothing new about states competing with one another to attract particular kinds of businesses. One of the first competitions was for the divorce business. (States competed by shortening residency requirements. Nevada won.) But now there is interest in more comprehensive involvement by state governments in shaping the economic evolution of their states.

Speaking with a tentativeness easily mistaken for weariness, Stevenson cites a doctrine economists devised to explain trade relations between nations -- the doctrine of comparative advantages. That is, particular nations -- or states -- are apt to have some particular advantages, natural or acquired, and should exploit them.

Stevenson is interested in using such resources as pension funds in a nonpolitical development corporation to impart momentum to promising state industries. With a candor that does him credit, but which qualifies his idea almost out of existence, he admits that it is difficult to prevent such a corporation from being politicized and institutionalizing the bail-out of failing industries.

Although Thompson is not running away from Reaganomics, neither is he running as a Reaganite. Stevenson has had a hard time sharpening the issues because Thompson, who radiates animal energy, thinks government should, too. The anti-government rhetoric that dominated so many races in 1980 is rare this year.

Thompson rightly stresses the limits to what can be done in Springfield to resuscitate, say, Peoria. (Peoria is home of the Caterpillar Corp.. Its sales to OPEC and Third World nations have slowed as oil and commodity prices have fallen.) But Thompson is nimble with this year's most fashionable political word: "infrastructure." Infrastructures (roads, bridges, schools, etc.) are Good Things.

In Illinois, as in other places, the closer and longer you look at the races, the fewer national and more local determinants you see. I grew up in central Illinois when an Adlai Stevenson was governor. I banged my rattle on my crib, demanding silence so I could nap, but the big people went on complaining loudly: "Your shock absorbers tell you when you leave Indiana and enter Illinois -- the roads are rougher."

Today the same charge is echoing across my native heath. That is as it should be, because roads are something about which a governor can do something.