April 17, 2012 In a conversation about what qualities Mitt Romney, the presumptive GOP nominee, might seek in a person to fill out his national ticket, GOP consultant Mike Murphy told NPR's Melissa Block the worse thing would be to go for the political equivalent of a sugar high. That happened in 2008 with Sarah Palin. He thinks the GOP learned its lesson. Thus, he thinks Sen. Rob Portman looms large for Romney.