Donald Trump and Hillary Clinton are beating their rivals by double digits in Pennsylvania ahead of the state's primary Tuesday, according to a new NBC News/Wall Street Journal/Marist poll.

Trump gets support from 45 percent of likely Republican primary voters in the state, followed by Texas Sen. Ted Cruz at 27 percent and Ohio Gov. John Kasich at 24 percent.

As in other nominating contests, the bombastic developer/entertainer performs best among men (52 percent) and voters without college degrees (52 percent). He also leads among those who say they are "strongly" behind their choice and dominates the Northeastern region of the state, with 52 percent of voters there.

Trump gets his worst numbers among the better-educated, women and in the Philadelphia suburbs, though he is taking a little more than a third of the vote even in these demographics, showing his overall strength. He wins 37 percent of college graduates, 39 percent of women, and white evangelicals (40 percent, but still better than Cruz's 36 percent). Trump's weakest-performing region is the Philadelphia suburbs – he edges Kasich there, 38 percent to 34 percent.

In the Pennsylvania Democratic race, Hillary Clinton is ahead of Bernie Sanders 55 percent to 40 percent among likely voters

Clinton leads among African Americans (67 percent to 29 percent); those ages 45 and older (66 percent to 28 percent); women (62 percent to 34 percent); self-identified Democrats (60 percent to 36 percent) and those strongly supporting a candidate (59 percent to 41 percent).

Sanders holds the edge among those who are under 45 (60 percent to 37 percent), those who are "very liberal" (58 percent to 41 percent), and men (55 percent to 39 percent).

He also has an edge with those who describe themselves as independents (55 percent to 39 percent). Only registered Democrats may vote in the party's "closed" primary in Pennsylvania, but self-identification is often used in polls – even in states where one must be registered with a party - as a marker of the relative partisanship of groups of voters.

The poll is based on interviews between April 18-20 with 734 likely Democratic primary voters, with a margin-of-error of +/- 3.6 percentage points, and 571 likely Republican voters, with a margin of error of +/- 4.1 percentage points.