Polls open for primary day in a string of East Coast states including Pennsylvania and Maryland, where front-runners Donald Trump and Hillary Clinton are looking to solidify their leads. Rough Cut (no reporter narration).
ROUGH CUT (NO REPORTER NARRATION) Donald Trump is poised to extend his lead in the Republican presidential race in a string of East Coast primaries on Tuesday, but a complicated contest in Pennsylvania, the day's biggest prize, will test his recently reorganized campaign. The state features the sort of complex rules that Trump has repeatedly slammed for being "rigged" and that forced him this month to reshuffle his team to better compete with main rival Ted Cruz for the 1,237 delegates needed to win the nomination for the Nov. 8 election. Just 17 of the 71 Republican delegates up for grabs in Pennsylvania on Tuesday are allocated to the candidate who wins its primary. The rest - people who are elected directly by voters - are free agents, able to support anyone they choose at the Republican National Convention in July. Pennsylvania and other states holding primaries on Tuesday - Maryland, Delaware, Rhode Island and Connecticut - are favorable terrain for Trump. Opinion polls show him leading in all five, prompting Cruz and John Kasich, the third Republican in the race, to announce an anti-Trump alliance. On the Democratic side, Clinton also looks set to solidify her lead over U.S. Senator Bernie Sanders in Tuesday's contests. Clinton's campaign says the former secretary of state now has an essentially insurmountable lead over rival Bernie Sanders. The 74-year-old U.S. senator from Vermont has no plans to drop out of the race, according to his staff, who are counting on defying pollsters with some surprise wins on Tuesday.