No question. Dean was forced to do a Diane Sawyer TV interview with his wife to dispel spousal questions. I believe the contrived togetherness worked against Dean----he and Mrs Dean acted so lovey-dovey, viewers thought the two were about to experience connubial bliss on-camera.
I don't think there is any way for a couple to "fake it" for the amount of time it takes to be on the presidential campaign trail.
If the spouse doesn't totally support the candidate, it will eventually be obvious. I think the support is actually a lot more important than whether the two are even in love. Dean's wife seems to really love him, but it was obvious that she really didn't want to leave Vermont and be in the spotlight. On the other hand, back in 1992 when the Klintoons did their "60 Minutes" piece it was clear that Hitlery thought BJ was a POS, but she fully supported his run for the White House.