Rand Paul, son of Texas Rep. Ron Paul and a favorite of the Tea Party movement, has built a big lead over Secretary of State Trey Grayson in the race for the GOP Senate nomination in Kentucky, according to a SurveyUSA poll conducted April 9-11. The race has been depicted as a test of the movement's influence, pitting a candidate trying to capitalize on the voter anger it reflects against an establishment Republican who has won re-election to his position three times. Grayson has fought back with TV ads honing in on Paul's "strange ideas," such as saying "Paul even...