Among the candidates on the Republican primary ballot here Tuesday are a local congressman, the woman who succeeded him on the county commission, a part-time mayor and the chairman of a local historical society. There is also a husband and wife running separately.

All are aspiring to represent Pennsylvania at the Republican National Convention in Cleveland, where they could turn out to be some of the most influential delegates in the nation.

The bitter contest between Donald Trump, Sen. Ted Cruz of Texas and Ohio Gov. John Kasich could come down to the final few undecided delegates from places such as Pennsylvania. If Trump falls short of the 1,237 delegates needed to win the nomination outright, his team has vowed to launch a full-scale pressure campaign to win over dozens of the delegates elected in the state’s unusual primary.

While most states award convention delegates on a winner-take-all or proportional basis, 54 of Pennsylvania’s 71 delegates — three for each of 18 congressional districts — are officially unbound to a candidate and do not have to announce their intentions before Tuesday’s vote. The winners can vote for whomever they want at the convention.

“I picked a very interesting year to run,” said Larry Stohler, 71, a former Lebanon County commissioner who says he would vote at the convention for whichever candidate wins here in the 6th Congressional District — at least on the first ballot.

The Fix’s Chris Cillizza breaks down what’s at stake for Democrats and Republicans in the April 26 primaries. (Peter Stevenson/The Washington Post)

With Pennsylvania the next biggest prize on the calendar, Kasich huddled this past week with some delegate candidates in the Pittsburgh area but declined to name one supporting him. Trump has a full-time Pennsylvania director who has been recruiting potential delegate candidates since January.

But Cruz is the most organized here in wooing delegates, just as he has been in other states with complex selection rules. Even if Cruz loses to Trump here Tuesday, there is a chance that the 26 delegate candidates who say they support the senator could win and cast votes for him at the convention.

Lowman Henry, Cruz’s Pennsylvania director, is urging supporters to “vote four times for Ted Cruz” — once for the senator and three more times for Cruz-supporting delegate candidates, some of whom Cruz met with on Saturday in Pittsburgh.

“Each time we have an event we take time to meet with delegate candidates,” Henry said Saturday.

The Cruz campaign began circulating fliers to supporters this past week with a list of the candidates supporting him in 17 of the 18 congressional districts. Voters in two of the districts would have to write in the names of Cruz supporters to help him get his 26 delegates, according to the flier.

The complexities of the process mean Trump could once again come up short on delegates despite winning the popular vote. Campaign manager Corey Lewandowski told reporters after Trump’s victory in New York on Tuesday that Pennsylvania has “a very difficult process” of selecting delegates.

Donald Trump said that the delegate selection process in the upcoming Pennsylvania Republican primary is unfair at a campaign event in Indianapolis on April 20. (Reuters)

“I don’t want to get into the intricacies of our Pennsylvania strategy, but I think we’ll make sure people know who the Trump delegates are,” he said.

Kasich said while campaigning in Pennsylvania that nobody will earn the 1,237 delegates needed before the convention — and that some of the best-known Republican presidents won after contested conventions.

“[Dwight D.] Eisenhower is a perfect example,” he told voters in Media, Pa., on Thursday, noting that the 34th president won after multiple ballots. The same thing happened to Abraham Lincoln, he said: “He even printed up some phony ballots for the delegates — we’re not going to do that.”

Here in the 6th Congressional District — nicknamed “the Dragon District” for its curving, elongated shape — most of the contenders say that if elected, they would cast ballots for whoever wins the district or the state.

“Delegate candidates, particularly on the first ballot, should reflect the will of their voters,” said Rep. Ryan Costello (R-Pa.), the best-known local delegate candidate.

Costello served as a delegate in 2012 and decided to run again this year because “I didn’t want a delegate to basically say, ‘I’m for Candidate A only, and I won’t be for anyone else.’ Particularly if that person hasn’t won any states or didn’t perform well in the congressional district.”

Michelle Kichline, a Chester County council member, also plans to vote for whoever wins the district. If the convention goes to multiple ballots, she said, “I will not make a decision speaking to just one of the candidates.”

Costello says he has spent “zilch” on the race. A few delegate candidates emailed information to local Republicans, but mostly they are relying on word of mouth, interviews on talk radio shows and interviews in local newspapers.

And in a race that requires few qualifications beyond being a registered Republican, candidates are struggling to distinguish themselves.

Kichline pointed to her gender: “There’s not as many women running for this position, and I think it’s important that women be represented in the Republican Party,” she said.

Stohler touted his public service. In addition to being a county commissioner and Vietnam War veteran, “I’ve been a volunteer firefighter since I was 16,” he said in a telephone interview Wednesday.

Moments later, he got a fire call.

The husband-and-wife team of Robert and Mary Elizabeth Wert signed up with Cruz in January.

The senator’s campaign team “walked us through how to do this. They helped us every step of the way,” Robert Wert said. “So we appreciate that, and we’re loyal to him.”

The couple think they will win because “we have a lot of good friends in the area to help us,” Mary Elizabeth Wert said. Plus, she said they are popular on the local charity circuit, so “we’re getting out to different fundraisers and seeing people.”

“You’re allowed to vote for three delegates,” her husband added, “but we’re encouraging people to vote just for us.”

Wayne Buckwalter, a trust and states attorney, said he would vote for Trump “on every ballot.”

“I think that at least one out of three people in my district will vote for Trump, and I want to be that delegate,” Buckwalter said.

He met Trump’s state director, Ted Christian, in January and agreed to sign a document stating that “I pledge to cast ALL of my ballots to elect Donald J. Trump on every round of balloting at the 2016 Republican National Convention so that we can MAKE AMERICA GREAT AGAIN!”

Other Trump supporters running for delegate slots across the state have signed similar documents. But it is unclear what penalty the Trump supporters would face if they broke the pledge. Christian did not respond to multiple requests for comment.

Douglas Hager, who sits on the board of a local historical society, also plans to vote for whoever wins the district. But he has heard nothing from the presidential contenders.

“I must have leprosy,” he said. “I haven’t been contacted by anybody.”

Instead, Hager has been inundated by potential constituents pleading with him to vote for Trump.

“I just deleted them because it was getting a little out of hand,” he said. “I got so tired of it.”

Jenna Johnson in New York City, Sean Sullivan in Philadelphia and Katie Zezima in Monroeville, Pa., contributed to this report.