On a conference call with reporters this morning, McCain surrogate Congresswoman Heather Wilson said that John McCain would “like troops to come home earlier than 16 months if the conditions allow it. Senator Obama has said it’s a 16-month timeline no matter what.” In response to a follow-up question asking if it was “conceivable” that conditions could improve enough to allow the troops to come home in 16 months, Wilson said that Obama’s withdrawal plan is “based on a calendar, and John McCain believes that withdrawal must be based on conditions on the ground. Whether that happens in in 12 months, 16 months, or 24 months, the important thing is our troops come home with victory and America’s vital national interests secured.” Wilson, as well as McCain foreign policy adviser Randy Scheunemann did not directly say whether conditions could improve enough to withdraw in 16 months. Scheunemann emphasized that Obama favored “rigid date-driven unconditional timetable”, while McCain’s withdrawal would be based on two factors: “advice of the commanders on the ground” and the “security situation on the ground”. Commanders in Iraq have said that there’s “no way” to withdraw all combat troops within 16 months, as Obama has proposed. But it wasn’t clear whether Wilson was saying that “all combat troops” could be withdrawn in less than 16 months or if she was simply emphasizing the difference between McCain’s conditions-based withdrawal versus Obama’s time-based withdrawal. Update: McCain’s deputy communications director Michael Goldfarb calls to say that Wilson was simply making a rhetorical point: