Craig Crawford's Trail Mix

Sen. Hillary Clinton has had no trouble dominating the stage so far against her rivals in presidential debates, but this week she faces the toughest challenge of all — upstaging her husband.

Bill Clinton joins the New York Democrat tonight for a three-day, six-city swing through Iowa in what their operatives are billing as the couple’s first public campaigning together since she began running for the White House.

In a joint appearance last March in Selma, Ala., to commemorate the city’s civil rights legacy, Hillary did not fare too well in the reviews. This week’s Iowa stumping will test whether the ex-President and the former First Lady can seamlessly reverse roles.

Mindful of the pitfalls, the Clinton camp plans on having Bill strictly confine his remarks to talking up his wife’s biography. If they pull it off with no harm done, look for this road show to get a nationwide run.