The Associated Press has called Donald Trump and Hillary Clinton as the winners of the presidential primaries in Maryland based on the results of exit polling conducted for AP and television networks.

The State Board of Elections in Maryland did not release any vote count from the state's primary elections until 9 p.m., when polls closed in four Baltimore precincts that were ordered to remain open for one hour past the statewide poll close time of 8 p.m.

Read more: 4 Baltimore precincts will stay open until 9 p.m. due to voting problems Tuesday morning

Donald Trump has won the Republican presidential primaries in Pennsylvania, Connecticut as well as the projected win in Maryland, giving the billionaire businessman a boost in a critical night as he seeks to shut out his opponents.

Clinton entered Tuesday's five primaries having already accumulated 82 percent of the delegates needed to win her party's nomination. While she can't win enough delegates to officially knock Bernie Sanders out of the race this week, she can make it virtually impossible for him to catch up to her in the remaining contests.

Trump's win Tuesday lends a boost to his embattled campaign as it faces a growing challenge from rivals Ted Cruz and John Kasich, who announced this week that they are teaming up to thwart his rise.

ABC News projects Donald Trump will win Connecticut, Maryland and Pennsylvania GOP primaries https://t.co/3FWz5SV6V6 pic.twitter.com/ucp4cIswWi — ABC News Politics (@ABCPolitics) April 27, 2016

JUST IN: @ABC News projects Hillary Clinton will win the Maryland Democratic primary https://t.co/FJBmzICHxs pic.twitter.com/h2NkAJOGvo — ABC News Politics (@ABCPolitics) April 27, 2016

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