Donald Trump holds a campaign rally on April 21 in Harrisburg, Penn. | M. Scott Mahaskey/POLITICO How Pennsylvania could make Trump the GOP nominee

Continuing our POLITICO feature, where we dig into the latest polls and loop in other data streams to tell the story of the 2016 campaign. Here are five numbers to watch.





Pennsylvania — like a number of states, including Illinois — conducts what’s called a “loophole primary”: At the top of the primary ballot, voters in each party will choose their preferred candidate.

But at the bottom of the ballot are names of delegates to the party convention – and because of the Republicans’ unique rules, they are likely more consequential than the names at the top.

Donald Trump is likely to carry the state and win the 17 delegates awarded to the statewide victor. But 54 delegates – three for each of the state’s 18 congressional districts – are elected directly on the ballot. And they aren’t bound to vote for a candidate on the first ballot at the Republican national convention in Cleveland, as the state delegates are.

As of Friday afternoon, the Pittsburgh Tribune-Review had reached 135 of the 162 delegate candidates on the ballot to survey them about their intentions. Many of the candidates said they would support the presidential candidate who wins the vote at the top of the ballot in their respective districts.

But, unlike in a state like Illinois, where delegates are required to vote on the first ballot for the candidate for whom they’ve declared – the Pennsylvania delegates aren’t bound at all. They can change their minds between the primary and convention, and they’ll be lobbied furiously by both sides if Trump is just shy of the majority of the delegates on the first ballot.

That lobbying effort is starting in the pre-election phase: Our Principles PAC, an anti-Trump super PAC, says it’s running robocalls in some Pennsylvania districts urging voters to support certain delegate candidates in order to elect delegates who won’t back Trump on the first ballot.





Pennsylvania and Maryland are the most contested states for Republicans among the five voting next week.

Of the $2.7 million being spent on television and radio advertising across the five states, just under $2 million is in Pennsylvania alone – despite the loophole primary.

Trump is spending nearly $1.3 million on ads himself, according to data provided by The Tracking Firm, a group monitoring media buys.

He’s joined on the Pennsylvania airwaves by Ted Cruz, who is spending $561,000 there. Two super PACs backing Ohio Gov. John Kasich are spending a little under $200,000.

The only other state seeing significant ad spending is Maryland. Kasich and his allies are spending a combined $414,000, joined by the anti-Trump Our Principles PAC, which launched a nearly $250,000 paid-ad effort late this week.





Hillary Clinton is favored to win most, if not all, of the five state contests next week – despite a substantial spending advantage for Bernie Sanders.

Sanders has outspent Clinton in most of the recent contests, and he’s again shelling out significantly more money on advertising than Clinton: $6.6 million for Sanders, compared to $3.9 million for Clinton.

That includes big edges for Sanders in Connecticut ($1.6 million to $905,000), Pennsylvania ($4.2 million to $2.5 million) and Rhode Island ($441,000 to $266,000). In Maryland, where Clinton holds a larger lead in the polls, the spending is more comparable: $265,000 for Sanders, and $238,000 for Clinton. (Delaware is mostly covered by markets in Pennsylvania and Maryland.)





The gender gap in Pennsylvania appears wider than it was eight years ago, when Clinton carried the state, boosted by a coalition of female and white voters.

A Monmouth University poll out this week – which gave Clinton a 13-point lead overall – showed Clinton with a 29-point advantage among women, 61 percent to 32 percent. Sanders was ahead among men, 50 percent to 41 percent.

In 2008, Clinton beat Barack Obama among female voters, 56 percent to 44 percent, according to exit polls. Obama carried men – 53 percent to 46 percent – but it wasn’t enough to overcome Clinton’s victory among women.

According to POLITICO’s calculations, the difference between Sanders’ vote share among men and women in the 22 states where there have been exit polls is about 11 points: He’s won 48 percent of men in these states, compared to 37 percent of women.





Two of the five states holding primaries next Tuesday are also nominating candidates for Congress: Maryland and Pennsylvania.

The slate includes a number of closely watched primaries: In Democratic-leaning Maryland, there’s the closely watched Senate primary between Reps. Chris Van Hollen and Donna Edwards – which has also sparked congested races for their D.C.-area House seats. In Pennsylvania, Democrats Joe Sestak and Katie McGinty are battling for the right to take on GOP Sen. Pat Toomey, while Reps. Chaka Fattah (D) and Bill Shuster (R) face competitive primary challenges at the House level.

It’s perhaps surprising then that the most expensive race next Tuesday isn’t one of the ten presidential contests, nor is it one of the two competitive Democratic Senate primaries. It’s the Democratic primary for Van Hollen’s House seat, where five candidates are spending nearly $10 million combined on television and radio advertising.

Most voters in the 8th District – which stretches from tony northwest D.C. suburbs like Bethesda and Potomac, along East-West Highway to Silver Spring, then snakes north to include parts of Frederick County all the way to the Pennsylvania border – live in the expensive D.C. media market, the nation’s seventh-largest. But even by big-city standards, the race is setting records.

Wealthy businessman David Trone – who founded the Total Wine & More chain of wine, beer and liquor retailers – has already kicked in at least $12.7 million of his own money for his campaign. He accounts for about $7.1 million of the TV advertising.

Trone’s late entry – he only declared for the race in January – scrambled the contest. Former news anchor Kathleen Matthews – the wife of MSNBC host Chris Matthews – and liberal state Sen. Jamie Raskin were seen as the two top contenders prior to Trone’s candidacy, but they have struggled to keep pace with Trone. Matthews has spent about $1.7 million on advertising, while Raskin has spent just $641,000.

State Del. Kumar Barve ($179,000) and former Obama administration official Will Jawando ($144,000) have spent more modest amounts of advertising. State Del. Ana Sol Gutierrez and former State Department official Joel Rubin haven’t been on the air.

The district is solidly Democratic, so the winner of Tuesday’s primary will be heavily favored to win the seat. But the primary alone already includes more candidate spending than any congressional race in the 2014 cycle, according to data from the Center for Responsive Politics. (Then-House Speaker John Boehner’s race is listed as the most expensive, but about half of what’s listed as Boehner’s spending is actually contributions to the National Republican Congressional Committee.)

