The victories put Trump and Clinton ever closer to clinching their parties' nomination for president.

Both Trump and Clinton tweeted following the results.

Though Sanders won Rhode Island, Tuesday's results were still considered a major blow to his campaign. He and Ted Cruz sought to downplay their losses, with Cruz saying he would focus on contests in more "favorable terrain," like Indiana, which holds its primary next week.

Speaking to an audience in West Virginia following the release of the first results, Sanders, meanwhile, railed against the lack of fairness in primaries that don't allow independents - many of whom support Sanders - to vote for a Democrat or Republican candidate.

Hopes for a big win

While Clinton has already blown past rival Sanders in terms of number of delegates won, a five-state win on Tuesday would seemingly put the final nail in the coffin for Sanders' candidacy. Nonetheless, the Vermont senator has said he won't quit even if he doesn't win any of the races on Tuesday.

Trump, meanwhile, is still trying to pull ahead of opponents Ted Cruz and John Kasich, who in an unprecedented move this week announced they were joining forces in a bid to slow the New York billionaire's momentum.

Trump mocked his rivals' announcement, calling it an act of desperation. While the brash GOP frontrunner leads by a clear margin, he still has yet to obtain the 1,237 delegates he needs to win the nomination and could very well fall short of that number, leaving the door open for a contested convention in June. If that happens, he could lose the nomination.

blc/jr (AP, AFP)