Bernie Sanders came out victorious in the Democratic contest, beating Hillary Clinton with 53 percent of the vote.
Fifty-seven delegates were up for grabs on the Republican side; Democrats were fighting for 92.
Going into the Indiana primary, Trump had amassed 956 delegates, Ted Cruz 546, and John Kasich 153 out of the 1,237 needed to win the party nomination.
On the Democratic side, Clinton went in with 1,663 delegates and Sanders 1,367 out of the 2,383 needed. (This count does not include superdelegates, many of whom have pledged to vote for Clinton but can still change their minds.)
RNC chairman Reince Priebus said Trump was the "presumptive" nominee.
Indiana is one of the states in which Cruz and Kasich tested out their alliance against Trump. They agreed that only one of them would campaign in certain states in order for someone to take as many votes away from Trump as possible. Cruz was in charge of Indiana — Kasich did not campaign there.
Neither that plan nor his recent announcement that Carly Fiorina would be his running mate proved to be enough for Cruz to steal the spotlight away from Trump.