Coming off of his impressive victory in New York on Tuesday, Donald Trump would seem to have a much easier path  to the Republican nomination for president.

As of Thursday, he has 845 delegates on his way to the 1,237 needed to be the Republican nominee for president. And, sitting on the horizon is Pennsylvania with its whopping  71 delegates -- a state where he holds a solid lead in the polls.

>>How many delegates does Donald Trump, others have?

However Tuesday’s presidential primary vote isn't what concerns Trump's campaign. It's the other part of the ballot he is far more interested in.

Pennsylvania's Republican primary is unique in its rules and how it awards its delegates. It's those rules that have Donald Trump, Sen. Ted Cruz, (R-Texas), and Ohio Gov. John Kasich looking for pledges of support any where they can get them.

How the Pennsylvania Republican presidential primary works

There are 71 Pennsylvania Republican delegates. Of those 71, 17 are at-large and bonus delegates, meaning they go to the winner of the presidential primary preference vote – Donald Trump, Ted Cruz, John Kasich or, less likely, anyone else on the ballot.

Now here is where Pennsylvania is significantly different than other states in awarding delegates: The second part of Pennsylvania’s primary is the vote for the remaining 54 delegates. There are 162 people on the primary ballot who are running to be a GOP convention delegate. They are elected geographically by congressional district, three from each of Pennsylvania's 18 districts for a total of 54.

Those 54 are unpledged delegates, meaning those delegates are bound to no specific candidate and may vote for whomever they wish at the convention.

Voters in Pennsylvania will directly elect those 54 delegates to the national convention Tuesday, but unlike most states, they will have no idea which candidate a delegate will support since the voter will only see a list of delegate names to choose from on their ballot.

Whom the delegates support is not meant to be secret, many have made their choices public, but there is nothing on the Pennsylvania ballot that would direct voters to delegates backing a specific candidate.

So, there’s a chance that if the polls are correct, Trump could win the Pennsylvania primary, but could end up with only a handful of the 54 unpledged delegates supporting him.

According to Marc Meredith, an associate political science professor at the University of Pennsylvania, who was quoted in a Boston Globe story, it really does come down to a candidate’s ground game in a state – something Donald Trump has been shown to be deficient in.

“Systems like this favor people who have well organized campaigns and are backed by the party,” Meredith told The Globe. “Trump fits neither of those criteria, so he stands to have the most to lose.”

How does this affect the convention?

If Trump falls short of the 1,237 delegates needed to clinch the Republican nomination for president, then the convention becomes a contested one since Cruz will almost certainly fall short of 1,237. (There is no way for Kasich to get to 1,237 prior to the convention).

In that case, convention delegates will vote for the candidate they are bound to on the first ballot, but then are free to vote for whom they wish on subsequent ballots.

However, the Pennsylvania 54 are not bound by such rules, they may vote for whom they wish on the first ballot and any other ballots taken.

Is 54 a big number?  In this situation, it’s a huge one. It represents more unpledged delegates than any other state has. If Trump had those 54 delegates sewn up prior to the July, there’s likely no contested convention and he would be the party’s nominee.

According to an Associated Press report, Republican Party officials say they expect an onslaught of delegate persuasion to begin in earnest after the election. In fact, they’ve already heard stories of Trump and Cruz operatives phone potential delegates to secure pledges of support.