He was a candidate for the Colorado Party's nomination in the April 2008 presidential election. Initial results in the December 2007 party primary election showed rival candidate Blanca Ovelar, who is backed by President Nicanor Duarte, narrowly defeating Castiglioni; however, the result was disputed, leading to a recount.
He was a candidate for the Colorado Party's presidential nomination in the April 2008 election. The December 2007 primary election results were contested, leading to a recount after Blanca Ovelar, supported by President Nicanor Duarte, narrowly defeated Castiglioni.