Donald Trump won three out of the four states to vote in their primary elections on Tuesday (Michigan, Mississippi, and Hawaii). Cruz won the remaining state (Idaho) and took second place in the other three states.
Marco Rubio did not pick up a single delegate from any of the 4 states on Tuesday. Kasich fared only slightly better by picking up 17 delegates in a 3rd place finish in Michigan. Both candidates have no path to the nomination. The math just simply does not add up for them.
Despite the horrendous results for both Kasich and Rubio, the two candidates refuse to drop out of the race. There is speculation that the two bottom candidates are staying in the race to muddy the waters and continue to steal delegates away from both Donald Trump and Ted Cruz.
A Republican candidate needs 1,237 delegates to win the nomination outright. However, if no candidate reaches that magic number, the nomination process will come down to a brokered convention in which the delegates get to vote for whom they want. It effectively ignores the will of the majority of Republican voters and puts it back in the hands of the party elite.
The Republican establishment choices that remain in the race are both Kasich and Rubio. The public has wholeheartedly rejected both of those candidates as Kasich has failed to win a state and Rubio has only won in one state.
Kasich is staying in the race at least until his home state of Ohio, despite losing in the polls. Rubio is wanting to stay in the race through his home state of Florida despite falling support in the polls.
It is no secret that the Republican party despises Trump and fears Cruz. If Rubio and Kasich are able to win a random state or steal delegates, the Republican establishment gets a few steps closer to their ultimate goal: a brokered convention in which they can control the outcome.