Your guests probably won't want to spit, but they should have access to a dump bucket so they can pour out what is left in their glass and then move on to the next wine. They also should know that it is usual to pour only a splash in the bottom of the glass. This allows plenty of room to swirl without spilling, and wastes less wine when the time comes to pour it out. Don't expect guests to concentrate on tasting during the entire evening. After the initial interest in the wine subsides, bring out hot d'oeuvres and more elaborate nibbles.
People then can relax with a glass of the wine they like the best.
Called gougeres in French, these bite-size cheese puffs are a good accompaniment to wine. Be careful not to overbake them or they will dry out. They can be made ahead, kept in an airtight container and then re-crisped at 300 degrees. Preheat oven to 400. Bring to boil, whisking occasionally.