GOP presidential front-runner Donald Trump Donald John TrumpObama calls on Senate not to fill Ginsburg's vacancy until after election Planned Parenthood: 'The fate of our rights' depends on Ginsburg replacement Progressive group to spend M in ad campaign on Supreme Court vacancy MORE holds a 21-point lead over primary rival Ted Cruz Rafael (Ted) Edward CruzSenate Republicans face tough decision on replacing Ginsburg Cruz: Trump should nominate a Supreme Court justice next week Renewed focus on Trump's Supreme Court list after Ginsburg's death MORE, a new national poll finds.

A new NBC News/SurveyMonkey online tracking poll released Tuesday found Trump leading the Texas senator, 48 percent to 27 percent. Ohio Gov. John Kasich, who gained 2 points since last week, follows with 18 percent.

When it comes to the possibility of a contested convention, the survey found that a majority of registered Republicans and those who lean Republican, 57 percent, believe that Trump should win the nomination if he wins a plurality of delegates, even if he fails to capture a majority of delegates.

The survey also shows 52 percent of those same voters are happy with a general election match-up between Trump and Democratic presidential front-runner Hillary Clinton Hillary Diane Rodham ClintonWhat Senate Republicans have said about election-year Supreme Court vacancies Bipartisan praise pours in after Ginsburg's death Trump carries on with rally, unaware of Ginsburg's death MORE, while 30 percent would consider a third party candidate.

The poll was conducted online March 21–27 and surveyed 6,521 adults, including 5,741 who say they’re registered voters.