First ladies who faced the least public criticism picked "soft" causes, according to Michele Swers, an assistant professor of political science at Georgetown University. Lady Bird Johnson chose beautification; Betty Ford used her personal experience to highlight addiction; and Laura Bush, a former librarian, encouraged reading.
"She said very clearly she doesn't want a legislative role," Swers said. "She's not going to do a Hillary Clinton-style health care plan."
And despite Baldridge's notion that two can share diplomacy, Michelle Obama must not play too large a role.
"First ladies do have the ear of the president," she said. "She's not elected, and people are touchy about that. But I think she's a very smart woman and will watch herself."
The image makers will be watching, too, at classic events like the White House Easter egg hunt and the lighting of the Christmas tree.
"They will want to portray him [Barack Obama] as very inclusive, as Every Man," said Swers. "He has this background of a white mother and a Kenyan father, so showing him with the wife and two children makes him very acceptable to the broad American public."
But it is their youth that may largely distinguish the Obamas from nearly a half a century of presidents. Malia could be 18 and Sasha, 15, if their father sustains two terms in office -- old enough for Michelle Obama to think about another renaissance.
"These people are young, and they are going to have to think about their careers after the White House, when the kids are grown," said historian Berkowitz. "She could be the next senator from Illinois."
Ferdous D. Alfaruque assisted in research for this report.