In the fight for mail-in voting, we just gained a foot.

When the Republican Party wanted to challenge state laws that count ballots postmarked by Election Day but received afterward, it explained its reasoning in plain terms: "Democratic voters tend to mail their ballots later on average than Republican voters, which results in late-arriving ballots favoring Democratic candidates."

That admission tells you almost everything you need to know about the modern GOP's approach to elections. Over the last decade, Republicans have understood that close elections are decided as much by which votes count as by who voters prefer. They have prioritized gaining every advantage in election rules that they can find, no matter how small.

Like a sprinter seeking an edge from lighter shoes or more aerodynamic clothing, Republicans understand that the results of elections are measured in inches, not yards or feet.

They know that a single tweak to voting rules can be the difference between winning an individual race and controlling Congress. And so, for years, the party has waged a quiet but relentless legal campaign to reshape the rules governing how ballots are cast, counted and thrown out, always with an eye toward the margins.

As a lawyer, I have spent countless hours litigating to stop Republicans from gaining an advantage by disenfranchising voters. No issue has dominated the voting rights landscape over the last six years more than mail-in voting, and specifically, how mail-in ballots are accepted or rejected.

I have fought with Republicans over the procedures and standards for matching signatures on return envelopes. I have litigated whether ballots with missing dates should be rejected or counted. In both instances, we have won more often than we have lost.

The result has benefited voters and, by extension, democracy itself. These fights rarely make headlines in the legacy media, but they determine whether a ballot cast by an eligible voter ultimately counts.

In recent years, no issue has been a higher priority for Republicans than the question of so-called late-arriving ballots: Ballots postmarked on or before Election Day but received by election officials afterward.

The GOP has spent millions arguing in court that counting these ballots violates federal law. And my law firm has fought them every step of the way.

Earlier this month, the U.S. Supreme Court agreed with us and rejected the Republican Party's lawsuit challenging these laws. In a 5-4 decision, the Court held that laws in 19 states permitting these ballots to count can stand.

Writing for the majority and rejecting the GOP's argument that such laws violate the federal Election Day statute, Justice Barrett wrote that “the electorate’s choice is made when voting is complete, not when ballots are received.”

Since the ruling, Republican legal challenges to laws in California and Illinois that allow ballots received after Election Day to be counted have also been dismissed. Donald Trump may continue to spread lies and misinformation about the pace at which these states, and others, finish counting their mail-in votes, but he no longer has a legal argument to stop it.

There was even better news out of Kansas.

Last week, in a lawsuit brought by my law firm, a state judge blocked a law that eliminated a three-day grace period for mail-in ballots that were postmarked by Election Day but received afterward.

The court held that “the three-day grace period for mail-in ballots has significant value in protecting mail ballots from unpredictable mail delays.” The judge added that “Kansas voters who submit their lawful advance ballots by mail, who do their part and vote and timely return it, should be able to trust that their ballot will be counted.”

After the victory in Kansas, I expect further challenges to state laws that limit the counting of these ballots. Such lawsuits are not guaranteed to succeed, but they stand a good chance in states where mail-in voting is an important part of the election process and where mail delivery is unpredictable.

But litigation should not be the only tool.

In the meantime, there are at least seven states where Democrats control both the legislature and the governorship and could change their own laws to count late-arriving ballots without waiting for a courtroom victory: Colorado, Connecticut, Delaware, Hawaii, Maine, New Mexico, and Rhode Island. Democratic leadership in these states should use this moment to enact a grace period at least as generous as Kansas's.

The larger lesson for Democrats is clear: Elections are not only won by persuading voters. They are won, and sometimes lost, in the fine print of statutes governing signatures, dates and deadlines that most Americans never read and few politicians ever discuss in public.

Republicans have understood and prioritized this for a decade and built an entire legal strategy around it. Democrats and voting rights advocates have too often played defense — case by case, state by state.

The recent wins on late-arriving ballots, at the Supreme Court and in Kansas, are a reminder that this fight is winnable — but we must be in the fight to win it. It is time we use every tool available, including litigation, legislation and advocacy, to gain the inches needed to protect free and fair elections this November and beyond.

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