The candidate was at a loss for words Tuesday, which in this campaign is a rare occurrence.
Standing in a packed gym in wind-swept Midwest oil country, Barack Obama was trying to explain how he and the 72-year-old white woman in the audience, with her hair band and spangly blue cardigan, happen to be related.
Obama had traveled here to his grandfather's birthplace to make a point about humble beginnings and possibility, about unity and shared purpose, and he was using his family's roots in deeply Republican Kansas as an illustration. At least, he was trying to.
Something about the McCurry family and a woman named Ruth, Obama began, tentative. She "was my grandfather's aunt, right? My grandmother's first cousin? . . . We're going through my family tree, trying to figure it all out."
The Illinois senator never got it quite right, but Margaret McCurry Wolf of Hutchinson, Kan. -- looking extremely proud and a little bit flustered -- was willing to explain their bond to anyone who asked.
"His grandmother is my first cousin," said Wolf, who had switched her voter registration from Republican to Democrat a month ago so she could caucus for Obama on Feb. 5. "I want him to make it so bad. I pray daily for him."
The candidate is not in South Carolina anymore, where African Americans helped him to victory in the primary on Saturday. When he talks inclusiveness in El Do-RAY-do (population 12,000, 94% white), he means something just a little bit different.
At least that's what Kansas Gov. Kathleen Sebelius stressed, when she joined Obama on Tuesday to announce her endorsement. A Democrat who once picked a former state GOP chairman for a running mate, Sebelius has gained national notice for her success in one of the most Republican states in America.
"Barack Obama has Midwestern values, values that we know about," Sebelius said. "He got them from his grandparents and from his mom," the Kansas branch of Obama's multiracial family. (His mother was white; his father was a black Kenyan.)
"He understands how to bring people together across party lines," she said. "He knows about not just working for the individual good but working for the common good . . . the kinds of values we believe in here in the heartland."
Stanley and Madelyn Dunham, Obama's maternal grandparents, came of age here during the Great Depression. As a young man, his grandfather "found odd jobs on small farms and oil rigs, always dodging the bank failures and foreclosures that were sweeping the nation at the time," Obama said Tuesday.
They married in the early days of World War II. Stanley enlisted in the Army shortly after Pearl Harbor was bombed, and he served under Gen. George S. Patton. Obama's mother was born on the Army base Ft. Leavenworth, and Madelyn worked on a bomber assembly line.
Obama, who was born in Hawaii, made his first pilgrimage to El Dorado some 60 years later, he said, living proof that his grandparents' dream was realized -- go to school on the GI Bill, buy a house through the Federal Housing Authority, send their daughter off to college. The Dunhams helped raise Obama after his mother's marriage broke up when he was 2.
"They were able to ride that upward mobility and help me get an education," he said on the plane from Washington. And he came here this day to highlight the small-town virtues of hard work and opportunity, the "ones that we need to rediscover."