Texas Senator Ted Cruz has a double digit advantage over Donald Trump in Wisconsin, less than a week before that state's primary. Party bosses meantime are trying to ensure a united front after the voting.
FOX's Jared Halpern has more from Washington:
The Republican frontrunner spent yesterday here in D.C.
Donald Trump meeting with national security advisers and a sitdown with Republican National Committee chairman Reince Preibus:
(Trump) "It's really a unity meeting. We're leading by a lot. We have far and away the most delegates. Millions and millions of votes more than anybody else."
But the meeting comes as Trump and his Republican competitors have backed away from a pledge to support whoever wins the nomination and a growing possibility no candidate secures 1,237 delegates before the July convention.
In Washington, Jared Halpern, FOX News.