Valerie Paget and Tracie Jones will be greeted at a 3 p.m. rally in Palo Alto led by the Raging Grannies, a feisty group of social justice activists, as they walk up El Camino Real toward San Francisco.
The grannies plan to don holiday costumes and sing a mix of Christmas carols and songs calling for marriage rights for gay and lesbian couples.
"This is our moment to stand strong, to refuse to accept a California where discrimination is enshrined in our constitution," reads a passage on the marchers' Web site, Revoke8.blogspot.com. The site tracks their progress through the state.
The marchers will arrive on the steps of the state Supreme Court on Friday when the couple says they will deliver a petition to revoke Proposition 8 that has been signed by more than 300,000 people.
The proposition, approved by 52 percent of voters on Nov. 4, changed the California Constitution to restrict the definition of marriage to a union between a man and a woman.
The women, who were married in Canada in April, began their 450-mile march in Los Angeles on Nov. 17.