Eight rules to help you understand what campaign money tells us — and what it doesn't

Every election season, news stories report on how much money candidates are raising and spending. In Ohio, more than $130 million was spent by outside groups in one U.S. Senate race in 2026. For most people, it can be hard to know what those numbers really mean or why they matter. A political scientist says there are eight basic rules that can help anyone understand campaign money.

Campaign money has changed a lot in the past 20 years. In the most competitive races, outside groups now spend more money than the candidates themselves. These groups — called Super PACs or 'dark money' groups — can pour millions of dollars into a race very quickly. This puts pressure on candidates to raise even more money just to keep up.

According to the Center for Responsive Politics, $9.5 billion was spent on congressional elections in 2024, up from $8.8 billion in 2020. Over the past decade, total spending has nearly doubled — from about $5.1 billion in 2014 to $9.5 billion in 2024. Fewer seats are truly competitive today, so most of that money goes to just a handful of races. This means individual races are getting more and more expensive.

In most congressional races, the candidate who raises the most money wins more than 90% of the time. But most of those races already have a popular incumbent who is almost certain to win. Those candidates raise a lot of money because people know they will win — not the other way around. Raising more money does not cause a candidate to win; winning causes them to raise more money.

The most competitive races draw the most money from outside groups and out-of-state donors. In these races, the candidate raising the most is usually the one who needs it most. Raising $500,000 more than your opponent matters a lot in a small race, but much less when both candidates have raised $20 million. The closer the race, the more the money flows in from all directions.

Where campaign money comes from matters a great deal. If a candidate raises money from people outside their district, those donors cannot vote for them. But when a candidate raises money from people in their own community, those same people are likely to vote and campaign for them too. Local donations are often a strong sign of real, ground-level support.

Some candidates brag about getting most of their money from small donations. U.S. Rep. Alexandria Ocasio-Cortez, a Democrat from New York, says her average donation is just $21. Candidates who attract many small donors tend to have views that are more strongly progressive or conservative than the average candidate. However, many of these small donors don't even live in the candidate's district.

Super PACs are political groups that can spend money supporting or opposing candidates, but they cannot give money directly to candidates or talk strategy with them. It is generally better for a candidate to have money in their own campaign fund because they know best how to use it. Still, Super PACs can raise unlimited amounts from a single donor and quickly change a race with a large advertising buy. A single wealthy donor can fund a huge ad campaign almost overnight.

Political parties work differently from Super PACs when it comes to spending. The Supreme Court recently got rid of limits on how much parties can spend to help their candidates. Parties have larger, more experienced staffs than Super PACs, and they have access to voter information that Super PACs do not. Parties and candidates can also get discounts on advertising that outside groups cannot receive.

The Federal Election Commission requires anyone who gives more than $200 to a federal candidate to report their employer. Some reports list how much money candidates get from employees of certain companies, but this can be misleading. Just because someone works at a company does not mean they are giving money to help that company. The most common job titles listed by donors are 'retired' and 'self-employed' — categories so broad they don't tell us very much at all.