ABC News May 1, 2016

Trump Holds 15-Point Lead Over Cruz in Indiana Ahead of Primary

WATCH: Donald Trump Hopes Indiana Victory Secures Nomination

Donald Trump holds a 15 percentage point lead over Texas Sen. Ted Cruz in Indiana ahead of the state's Republican primary this Tuesday, according to a new poll from NBC/WSJ/Marist released Sunday morning.

Trump earned 49 percent support in the new poll, while Cruz garnered 34 percent and John Kasich had 13 percent.

The result would help pave the way to the GOP presidential nomination for the real estate mogul, padding his delegate lead and giving him a viable way to become the "presumptive nominee" by clinching 1,237 pledged delegates after California and New Jersey vote on June 7.

Why Indiana Could Make or Break Trump's Path to the Nomination Ted Cruz and Donald Trump Battle Before Indiana Primary Indiana Governor 'Pleased to Support' Ted Cruz

Indiana is a winner-take-most state worth 57 delegates -- 30 delegates to the statewide winner and 27 delegates based on the winners of each congressional district. Even if Trump loses the state, he will still have a viable path to winning the nomination, using unbound delegates from states like Pennsylvania, North Dakota and Louisiana.

The poll also shows a majority of GOP voters in Indiana disapprove of the attempted alliance between Cruz and Kasich to consolidate the anti-Trump vote in the state. Fifty-eight percent of them say they disapprove of the combined effort to block Trump, while only 22 percent said it was a major factor in their vote.

On the Democratic side, Hillary Clinton and Bernie Sanders are locked in a tight race in the Hoosier State. The poll has Clinton with 50 percent support, while Sanders garners 46 percent -- close enough to be within the poll's margin of error.

Indiana is a proportional state worth 83 pledged delegates for the Democrats. After Indiana votes, it will be mathematically impossible for Sanders to clinch the Democratic nomination using only pledged delegates -- and will need help from the superdelegates to win.

Sanders needs to win remaining states by an average of 30 percentage points to lead the pledged delegate count.