Imagine if the government said that only the first 12 people who arrive at church on Sunday get to stay for the entire sermon or that only the first 12 people who arrive at the polls on Election Day get to vote for every office.

Nobody would doubt that these restrictions are unconstitutional. And the reason is simple: The Constitution protects everyone equally — it does not allow rights to be dished out on a first-come, first-served basis.

Apparently nobody ever shared this common-sense principle with the Minnesota Legislature, because Minnesota law does exactly that when it comes to making political contributions in state elections. In campaigns for the statehouse, Minnesota law allows only the first 12 citizens to donate $1,000 to the candidate of their choice. Everyone afterward may donate only $500.

This law — called the "special sources limit" — is even more extreme than the federal contribution limits that the U.S. Supreme Court held unconstitutional just last week in McCutcheon vs. FEC. While that case was about wealthy individuals making large contributions to lots of candidates, Minnesota's law applies even to donors who make just one political contribution.

This restriction has serious consequences for political candidates. In elections, candidates need to be able to raise money to get their messages out to the voting public. It costs money to print fliers, run ads or buy gas to travel to campaign stops and tell voters why they should vote for one candidate rather than another.

By arbitrarily reducing the ability of candidates to raise political contributions, Minnesota's special-sources limit forces candidates to spend more time raising contributions and less time campaigning. That leaves voters with less information on which to cast their votes.

But the freedom to make political contributions is not just important to candidates and voters, it is also important to donors themselves. Political contributions are a venerable form of peaceful political association. They allow contributors to participate in the political process by supporting candidates whose messages they believe in.

Those contributors include Doug Seaton and Van Carlson, two Minnesotans who care deeply about public policy and the state's future. They believe that the best way to support the candidates they believe in is to give those candidates contributions so they can mount effective campaigns. But both Seaton and Carlson have had contributions rejected because the candidate they supported had already reached the special-sources limit.

Seaton and Carlson think it is outrageous that because other people have already donated to a candidate, their donations are subject to additional limits. Why is it OK for a candidate's first 12 donors to make $1,000 contributions, but not OK for anyone else to do so? It is just an arbitrary limit on First Amendment rights.

Allowing 12 lucky Minnesotans to contribute more than others in an election is not just arbitrary — it is unconstitutional. As the Supreme Court reiterated in McCutcheon, the only limits on campaign contributions that are constitutionally acceptable are limits that reduce "corruption or the appearance of corruption."

But the special-sources limit cannot possibly affect corruption. The Minnesota Legislature has already determined that $1,000 contributions are not corrupting — that is why it already allows up to 12 contributors to make $1,000 contributions. There is absolutely no reason to believe that the 13th person to make a $1,000 contribution is corrupting, while the first 12 contributions were perfectly all right.

Thankfully, Seaton and Carlson aren't going to stand for this arbitrary restriction — they have chosen to fight back. Today, Seaton, Carlson and two candidates for state office — Linda Runbeck and Scott Dutcher — have teamed up with the Institute for Justice, a nonprofit, public-interest law firm, to challenge Minnesota's special-sources limit in federal court. Their lawsuit will be the first opportunity for a federal court to apply the Supreme Court's ruling in McCutcheon to a state campaign-finance law.

Everyone benefits when people are free to participate in elections. When Carlson and Seaton's lawsuit defeats the special-sources limit, First Amendment rights will be available to anyone wishing to help candidates spread their message to voters — not just the first lucky 12.

Katelynn McBride is an attorney at the Institute for Justice and one of the attorneys representing the donors and candidates. The Institute for Justice litigates campaign-finance cases nationwide.