Sanz is not named as a protagonist of the turmoil which rocked top layers of the party, apart that he resigned from the Navarrese jefatura. It seems he did not fall from grace, as in 1902 he was considered member of an auxiliary junta, to be set up as assistance to the ailing Barrio. However, having lost the parliamentary mandate in 1903 he lost also prestigious position within the executive, especially that his friend de Cerralbo was also sidetracked and the party was controlled by a new team. In 1904 Sanz attempted to re-enter the Cortes; instead of Congreso de Diputados he targeted the Senate, fielding his candidature in Navarre. Instead of popular vote, members of the upper chamber were selected by a pre-defined group of electors, named compromisarios; accordingly, the electoral campaign was all about behind-the-stage dealings. Details of the bid are not clear, except that Sanz was endorsed as a Carlist candidate; at that time he was already sort of an iconic Navarrese figure, acknowledged even in not necessarily hostile press couplets. The negotiations must have proven unsuccessful, as he withdrew shortly before the process was concluded. In the mid-1900 he generally disengaged himself from great politics and focused on the Toledan milieu. Apart from rising to executive of the local Asociación de Misiones Pedagógicas, in 1906 he entered Junta Municipal de Toledo and in 1908 became adjunto del Juzgado Municipal. Having engaged in setting up the municipal Cámara de Comercio, in the early 1910s he emerged as its first president. In 1914 Sanz resumed his Senate bid, again from Navarre. There is no information on the background of the campaign, though apparently this time the backstage haggling proved successful: he was elected among 3 candidates who enjoyed massive advantage over the remaining contenders. The victory again proved to be the first one in a string of successive triumphs: Sanz got his mandate prolonged in 1916, 1918 and 1919. His 4 terms came to an end in 1920; it is not clear whether he lost or decided to terminate the parliamentarian career. Unlike in case of his deputy record, Sanz's stand in the upper chamber was not passive. Though in terms of legal initiatives he is noted only for fathering a draft law related to officer retirement rules, the project he eventually withdrew, Sanz engaged in a number of army-related discussions – he contributed to debates on internal organization, military academies, remuneration and awards, war in Morocco, retirement or military justice.