Smashed this together from Scriptable’s example plus my bitbar version

predictit-2020-scriptable.js

let getCandidateByShortname = (candidates, shortName) =>
  candidates.find((candidate) => candidate.shortName === shortName);

let floatsToInts = (candidate) => ({
  ...candidate,
  lastTradePrice: round(candidate.lastTradePrice),
  lastClosePrice: round(candidate.lastClosePrice),
});

let round = (float) => Math.round(float * 100);

let changeToday = (now, close) => {
  if (now === close) {
    return "";
  } else if (now - close > 0) {
    return ` (↑${Math.abs(now - close)})`;
  } else {
    return ` (↓${Math.abs(now - close)})`;
  }
};


let createWidget = results => {
	
	const [biden, trump] = ["Biden", "Trump"]
		.map((shortName) => getCandidateByShortname(results.contracts, shortName))
		.map(floatsToInts);

	const leadNow = biden.lastTradePrice - trump.lastTradePrice;
	const leadAtLastClose = biden.lastClosePrice - trump.lastClosePrice;


	let w = new ListWidget()

	let emoji = w.addText("🗳")
	emoji.applyHeadlineTextStyling();
	
	w.addSpacer(16)
	
	let titleTxt = w.addText(`${leadNow}${changeToday(leadNow, leadAtLastClose)}`)
	titleTxt.applyHeadlineTextStyling();
	
	w.addSpacer(8);
  
	[biden, trump].forEach((candidate) => {
		let text = w.addText(`${candidate.lastTradePrice} ${candidate.shortName}${changeToday(
			candidate.lastTradePrice,
          candidate.lastClosePrice
		)}`)
		text.applySubheadlineTextStyling()
		text.textOpacity = 0.8;
	});
	
	w.addSpacer()
	
	w.url = "https://www.predictit.org/markets/detail/3698"

  return w
}
  
const loadResults = async () => {
  let url = "https://www.predictit.org/api/marketdata/markets/3698"
  let req = new Request(url)
  let json = await req.loadJSON()
  return json
}

let results = await loadResults()

let widget = createWidget(results)

if (config.runsInWidget) {
  Script.setWidget(widget)
  Script.complete()
} else {
	widget.presentSmall()
}