Those who’ve been following the Republican presidential nomination contest closely know that the next big question to be resolved is whether Donald Trump can secure support from 1,237 Republican National Convention delegates before the convention meets in July.

As an article in the latest Bloomberg Businessweek reminds us, the answer to that question involves more than just winning primaries and caucuses.

Aldridk Gessa has been campaigning for months. She walked door to door in the dead of winter collecting signatures to get her name on the ballot. She’s handed out leaflets, spoken at local events, and appeared on regional TV and radio programs to make her pitch. Her goal: winning a place as a Republican delegate from Pennsylvania’s 2nd Congressional District so she can attend the Republican National Convention in July.

Gessa is one of 163 people running for 54 delegate spots alongside presidential candidates on the April 26 Pennsylvania primary ballot. Most of the 2,472 Republican national delegates will be bound to support candidates on the first convention ballot according to the popular vote in their state. In contrast, Pennsylvania’s elected delegates will be free to vote for whomever they wish, making them especially important in this year’s tight race. They will make up about a third of the approximately 175 free agents who will travel to the convention in Cleveland, more than from any other state. “We actually might be those people who decide the next Republican nominee,” says Gessa, 44, a Ted Cruz supporter.

With three candidates still in the race, it’s possible front runner Donald Trump may fall short of the 1,237 delegates he needs to clinch the nomination outright. The last time none of the Republican candidates amassed enough committed delegates before the national convention was in 1976, when Ronald Reagan mounted a challenge to unseat incumbent President Gerald Ford. Just three weeks before that year’s gathering in Kansas City, Mo., Reagan shocked his fellow conservatives by recruiting moderate Pennsylvania Senator Richard Schweiker as his running mate. It was an unexpected gambit with a clear motive: wooing unbound delegates from Schweiker’s home state. Reagan ultimately failed, losing to Ford on the first ballot.

This year, Trump, Cruz, and John Kasich are going straight to the would-be delegates.