Why Winning Pennsylvania's Popular Vote Isn’t Enough to Win Its GOP Delegates

— -- When Republican voters head to the polls to cast their vote in the presidential primary in Pennsylvania on Tuesday, helping to nominate the presidential candidate of their choosing is not as simple as selecting the candidate’s name on the ballot.

Because of Pennsylvania’s unusual delegate allocation process, what will carry more weight is the delegates who voters select to represent their district at the Republican convention. And the three remaining GOP presidential campaigns are waging shadow campaigns to get friendly delegates elected.

Delegate Free Agents

In addition to casting a vote for their presidential candidate of choice, voters in each of Pennsylvania’s 18 districts will also select three delegates to represent them at the GOP convention on Tuesday’s ballot. The 54 delegates selected on Tuesday are unbound, meaning they are free to vote for the candidate of their choosing regardless of the outcome of the state’s popular vote on the first ballot at the convention.

There are 17 other delegates who are bound on the first ballot to vote for the candidate who wins the state’s popular vote. After the first ballot, those delegates are unbound. Three of the state’s bound delegates are Republican National Committee members, while 14 others will be chosen by the 350 members of the state Republican Party at a summer meeting in May.

Shadow Campaigns Underway

Supporters of the three remaining GOP candidates are working to win over these unbound delegates, whose support could push front-runner Donald Trump close to clinching a majority of delegates on the convention’s first ballot. It is mathematically impossible for Trump’s opponents, Texas Sen. Ted Cruz and Ohio Gov. John Kasich, to nab the nomination on the first ballot, which means they could benefit from friendly delegates as they try to win on subsequent ballots.

Cruz’s campaign began the process of identifying delegate candidates partial to Cruz in each of the state’s congressional districts -- save for one in which the spots were uncontested -- around Thanksgiving, according to Cruz’s Pennsylvania state chairman, Lowman Henry.

The campaign, Henry told ABC News, recruited Pennsylvanians to collect signatures before a mid-February deadline to appear on ballots, and has more recently focused on telling Cruz supporters which delegates to vote for, since actual ballots will not identify them as connected to a certain candidate. Henry said the Cruz campaign had identified 28 candidates who would support the senator on the first ballot and “another couple dozen” who would flip to Cruz on subsequent ballots.

“Voters are very confused because this process really hasn’t come into play in Pennsylvania for 40 years,” Henry said. “Which is why we’re working hard to educate voters that just voting for their respective candidate alone is not enough to ensure that that candidate gets voters.”

Carol Drewniak, an 11th District candidate who has been endorsed by the Cruz campaign, said the campaign has hosted several conference calls to brief her and other candidates on resources available to them in building their campaigns.

“They have offered to hand out some fliers and literature at the polls and they gave us resources, walking lists and volunteers at our districts that we can reach out,” Drewniak told ABC News.

Trump’s campaign has had little contact with Pennsylvania delegate candidates who say they support the billionaire businessman, according to one of those candidates, Gabriel Keller, an IT worker and first-time candidate from Pine Township, Pennsylvania, outside Pittsburgh.

Keller told ABC News the Trump campaign reached out to him in December to encourage him to run; he said his only prior contact with the campaign had been signing up to help through its website. Since then, he has networked with other candidates who support Trump and are working through the process on their own. He said he had, on his own volition, made a website promoting the candidates, printed business cards and ordered yard signs and candy to distribute to voters along with literature at polling places next week. A donor, he said, helped finance part of his efforts.

A five-minute conference call organized by Trump’s campaign a week and a half ago did not offer much, Keller said. “It pretty much was a five-minute call that said, ‘Hey, we’re on your side, we’re going to help you get elected, don’t worry about it,’” he said.

Cruz and Kasich have personally met with groups of delegates in Pennsylvania, according to their campaigns -- Kasich for the first time on Tuesday morning in Pittsburgh. A surrogate for Cruz, former Republican presidential candidate Carly Fiorina, did the same on Tuesday, while national party committee members backing Kasich are meeting with delegates this week, the campaigns said.

Emmalee Kalmbach, a spokeswoman for Kasich, told ABC News the campaign’s delegate outreach in Pennsylvania had being going on for “quite some time” but that she did not have a specific date when it had started. The Ohio governor’s campaign has focused on convincing the delegate candidates already on the ballot to throw their support behind Kasich, she said.

Some Still Uncommitted

Even at this late stage, some delegates remain uncommitted.

“I’ve never been more undecided,” Mary Beth Doherty, a candidate for 17th District and a former Marco Rubio supporter, told ABC News. “I’m not opposed to anybody at this point but I do want to be convinced that our nominee can win in November.”

In the “handful” of calls Doherty says she’s received from voters curious to know why they should support her as an uncommitted delegate, Doherty said she asks voters who they are supporting and said whom the district and state choose in the popular vote will be two major contributors in whom she would ultimately support at the convention.

“The third is electability -- that’s my number one concern,” Doherty said.