Michigan’s Democratic rupture and Alaska’s ballot controversy could turn frustration into votes—and complicate predictions of a Democratic takeover.

The closing days of an election are supposed to be about delivering the message, mobilizing supporters, and getting voters to the polls. 

In Michigan and Alaska, Democrats are instead confronting developments that could give Republicans something especially valuable: a fresh reason for people to vote.

Neither episode guarantees a Republican victory. But both illustrate why predictions of Democratic control of Congress remain vulnerable to events that polling conducted days earlier cannot fully capture.

In Michigan, a shocking development: Democratic Congresswoman Haley Stevens has endorsed Republican Mike Rogers over Abdul El-Sayed, the Democrat who defeated her in the Senate primary. A planned display of Democratic unity instead became a public demonstration of division.

The public endorsement gives dissatisfied Democrats permission to cross party lines. Stevens says she remains a Democrat. Her message allows voters to support Rogers without embracing every Republican policy or endorsing everything President Trump has done.

That distinction could matter a great deal among voters who share her concerns about Mr. El-Sayed’s rhetoric and associations. Her support among Black and Jewish primary voters makes the rupture particularly uncomfortable for Democrats trying to assemble their winning coalition.

Some persuadable voters may indeed switch to Rogers. Others may vote in some contests while leaving the Senate race blank. Still others may need less encouragement to stay home. Rogers benefits from any combination that reduces his opponent’s advantage.

Alaska presents a different, potentially more combustible problem.

A recent blockbuster New York Times investigation described an effort involving Democratic operatives and Mary Peltola campaign aides to recruit spoiler candidates, including another Dan Sullivan. The apparent objective was to exploit confusion with Republican Senator Dan Sullivan’s name.

Peltola denies knowing about the recruitment. Her personal responsibility remains disputed, and criminal wrongdoing has not been established. But those qualifications do not diminish the seriousness of deliberately trying to make voters select someone they never intended to support.

Since Peltola was most likely to benefit, had the scheme succeeded, she may find it difficult to rise above the blowback, legal or otherwise.

For voters, the insult may be easier to understand than the legal arguments. A campaign can disagree with your priorities. It can criticize your preferred candidate. But an operation designed around mistaken identity appears to say something uglier: you’re stupid and we can fool you.

That reaction can drive voter participation, rather than simple disillusionment. An independent who was considering skipping Tuesday’s election might decide to show up. A Republican who liked Peltola personally might return to Sullivan. A Democrat troubled by the reported conduct might withhold support.

“Who benefits?” is a legitimate investigative starting point. Establishing individual responsibility requires further evidence, but voters do not need to suspend their judgment about the tactic while investigators examine communications and financing.

Publicity may also help voters distinguish the two Sullivans. Alaska’s ranked-choice system can preserve a vote for the incumbent when a voter ranks him after an eliminated candidate. Increased awareness could therefore reduce the confusion the alleged strategy sought to exploit.

In worse news for Democrats, the electoral arithmetic favors taking small changes seriously. 

When someone switches from the Democrat to the Republican, the Republican’s raw margin improves by two votes. One additional Republican voter improves it by one. Across a close statewide contest, modest changes can determine the winner.

Early voting limits the available movement, however. 

Many ballots were cast before these developments, and older allegations against Peltola should not be counted as entirely new revelations. Nor should anyone assume that outrage travels only one way: Democratic campaigns will try to rally supporters against Republican attacks.

Still, Republicans have concrete reasons for encouragement.

Holding Alaska would deny Democrats a pickup. Winning Michigan would flip a Democratic seat, creating additional protection against Republican losses elsewhere. Together, those outcomes would substantially strengthen the Republican position in the Senate.

The House connection is less direct but still plausible. An otherwise reluctant Republican who turns out because of a Senate controversy can also support the party’s House candidate. Michigan offers opportunities for such effects across multiple districts; Alaska has one statewide House contest.

No scandal automatically delivers an election. But campaigns are contests of motivation as well as opinion. These developments give Republicans fresh arguments about judgment, trust, and respect for voters.

On Tuesday, a small number of newly determined voters could make a very large difference.

(Contributing writer, Brooke Bell)