Republican presidential candidate Dr. Ben Carson talks to pastors and community leaders during a meeting at the Bilingual Church in Baltimore, Maryland, May 7, 2015. No clear front-runner has emerged in the Republican field for 2016 in a new Quinnipiac University poll, which shows former neurosurgeon Ben Carson as one of the top five finishers, each with 10-percent support. The top five contenders are former Florida Gov. Jeb Bush, former Arkansas Gov. Mike Huckabee, Florida Sen. Marco Rubio and Wisconsin Gov. Scott Walker, apart from Carson, according to the national survey conducted May 19-26 among 1,711 voters across the country....