A new poll released Tuesday by the Pew Research Center shows American voters are more divided than ever when it comes to political ideology. The poll, which began in 1987, marks an 18-point disparity in value-related issues between Republicans and Democrats, up from just 11 percent in 2003. The poll has jumped in recent years: in 2009 it was 16 percent before reaching its highest level this year. One pollster said that “the parties are more polarized than” ever before in the 25 years of the poll. The poll also showed that a growing number of Americans identify as independents (38 percent) compared to Democrats (32 percent) or Republicans (24 percent).