http://www.realclearpolitics.com/article...29878.html
Note: Article doesn't mention Puerto Rico which votes Sunday. Rubio is heavy favorite there. Note that current rules require a candidate to win 8 states to have his name put into nomination. Its 10 Trump, 4 Cruz, 1 Rubio right now.

With the GOP field now down to a quartet, Donald Trump, Ted Cruz, Marco Rubio and John Kasich are competing in Maine, Kansas, Kentucky and Louisiana. Democrats Hillary Clinton and Bernie Sanders are vying for support in Nebraska, Kansas and Louisiana.

,,,,
Some states require candidates to get at least 20 percent of the vote to claim any delegates, but candidates in Kentucky must get just 5 percent of the statewide vote to get delegates, and in Kansas and Maine the bar is 10 percent. In Louisiana's primary, there is no threshold to earn a portion of the delegates.
....
Trump is the only one of the four to visit Kentucky, promising during a Louisville appearance that he'd lead a comeback for the state's struggling coal industry.

All four candidates have spent time in Louisiana, where Cruz hopes for strong support from born-again Christians, but so far Trump has been siphoning a considerable share of evangelicals.

Trump's "tapped into a level of frustration that transcends religiosity," said Ed Chervenak, who heads the University of New Orleans Survey Research Center.

Trump and Cruz both campaigned in Maine in the past week, but Rubio skipped the state.