PLOVER, Wis.

Tammy Baldwin, who has a very real chance of becoming the first openly gay or lesbian person elected to the United States Senate, stood with a 73-year-old potato farmer in his fields here the other day and asked him: “How hot am I?”

For the previous half-hour, the farmer had been boastfully showing Baldwin, 50, his equipment: the sorting machine, the stacking machine. And now, in response to her question, he nudged his thermometer close to her. I do mean thermometer, an infrared one, with which he’d just determined that the temperature of the dirt on this scorching July afternoon was 136 degrees.

He took a reading of Baldwin’s skin, which was a crackling 101.

“Wow,” she said, repeating a syllable that was getting a thorough workout as she deftly played a social role as traditional as any: the attractive younger woman stroking the older man’s pride. Her sexual orientation was irrelevant.

Because he didn’t care about it? Or didn’t even know? I had just a few minutes to chat with him before she and a few aides, doing a campaign swing through rural Wisconsin, arrived, and I got the sense that he was familiar only with her politics, the populist tone of which he said he liked.