Marchante was selected by his team to ride the 2006 Vuelta a España. During Stage 5 with 6 km to go he ride across to Sérgio Paulinho and David Arroyo who were the leaders on the road. Marchante rode the two off his wheel. With 3 km to go he was caught by two riders, Danilo Di Luca and Janez Brajkovič, Marchante tried to attack them but dropped off with the high pace. In the last kilometre he was passed by Andrey Kashechkin finishing fourth in the stage.[4] Later in the race during Stage 18 Marchante was the only rider who was working with Alejandro Valverde to catch Alexandre Vinokourov who was up the road.[5]
Following on from his great 2006 season he was named as a key domestique in the Grand Tours for 2007.[6]