Republican presidential candidate former UN Ambassador Nikki Haley speaks at a caucus night party in West Des Moines, Iowa, Jan. 15. AP-Yonhap

United States President Joe Biden and Republican challenger Donald Trump on Tuesday easily won their primaries in the battleground state of Pennsylvania according to Edison Research, but thousands cast votes for former candidate Nikki Haley.

Pennsylvania, with 19 Electoral College votes toward the 270 needed to win, is a top prize and a toss-up in the 2024 presidential election featuring a Biden-Trump rematch.

Tuesday's primary was one of the last tests of voter enthusiasm in a campaign marked by both candidates' low approval ratings.

With 95 percent of the votes counted, Biden got 920,274 votes, or 93.1 percent, according to state election data. Dean Phillips, a Democratic congressman who dropped out of the race, got 68,046 votes, or 6.9 percent, state data shows.

Trump got 786,485 votes, or 83.5 percent, with 95 percent of the votes counted, state data showed. Haley, who dropped out the race, got 155,829 votes, or 16.5 percent.

Outgoing U.S. Ambassador to the United Nations Nikki Haley talks with President Donald Trump in the Oval Office of the White House after the president accepted Haley's resignation in Washington, Oct. 9, 2018. Reuters-Yonhap

Haley, a former South Carolina governor and U.N. ambassador, remained on the Pennsylvania ballot after dropping out of the race in March. Primary voting in the state is confined to registered Republicans, locking out the independent voters who favored her.

Her substantive results show that some chunk of Republicans continues to be unhappy with Trump, who is on trial on 34 criminal counts in New York.

Muslim and Arab-American voters mounted an "Abandon Biden" campaign in Pennsylvania to protest the president's handling of the Gaza crisis. He faced similar efforts in battleground states like Arizona, Wisconsin and North Carolina, with the biggest turnout a 13 percent uncommitted vote in Michigan's primary.

Organizers in Pennsylvania were aiming to get 40,000 write-in "uncommitted" votes.

Those results are not expected to come on Tuesday night because they will have to be entered manually.

Supporters of U.S. President Joe Biden cheer as they await his speech about reproductive freedom at Hillsborough Community College-Dale Mabry Campus in Tampa, Florida, April 23. AFP-Yonhap

Biden clinched the Democratic nomination and Trump secured the Republican nod in early March, and neither faces serious opposition on the primary ballot.

In 2020, Biden won Pennsylvania by less than 1.5 percent, or roughly 80,000 votes. Trump beat Democrat Hillary Clinton there by fewer than 45,000 votes in 2016. Biden and Trump have visited the state in recent weeks and focused on the general election rather than Tuesday's vote.

Biden was born and spent part of his childhood in Scranton, Pennsylvania, and has for decades been a fixture in the politics of neighboring Delaware.

Incumbent U.S. Senator Bob Casey, a Democrat, and his Republican challenger, Dave McCormick, were both unopposed in their primaries. The race, which opinion polls show as close, could help decide whether Democrats retain control of the Senate. (Reuters)