For the past five months, real estate magnate Donald Trump has led all but two national polls of the Republican national primary. On Wednesday, a CNN/ORC poll found him with his largest lead yet: a 21-point advantage over Senator Ted Cruz (R-Texas), who himself has been surging in the polls of late. Trump was up three points from CNN's last survey in November. Many people are still asking themselves how this bombastic businessman could maintain frontrunner status this long. Trump has sold much of the Republican primary electorate on his ability to tackle the issues most concerning to Americans, with the economy and foreign affairs among them. Perceptions of his electability, favorability, and strategy on key areas have all improved considerably over the past six months. In many of these cases, he has seen dramatic shifts with the GOP electorate. Here are some of the findings: In December, 72% of registered Republicans view Trump favorably compared with only 51% who vie...