Eight U.S. states are asking to ban noncitizens from voting even though it is already illegal, and critics say it is part of a plan by Donald Trump and his Republican allies to challenge the presidential election result if he loses again on Nov. 5.

The states include two that are expected to help decide the election. The measures, on the Nov. 5 ballot, seek to amend state constitutions. Trump, the Republican Party candidate, says noncitizen votes could skew the election outcome.

Support from a majority of voters would mainly tweak state constitutions to say explicitly that only citizens can vote, a change critics say will have little practical effect, given that it is already illegal for noncitizens to vote in those states.

The proposals will be on the ballot in November in the swing states of North Carolina and Wisconsin as well as the solidly Republican states of Idaho, Iowa, Kentucky, Missouri, Oklahoma and South Carolina.

Supporters say the measures address voter concerns spawned by record levels of illegal crossings at the U.S.-Mexico border during Democratic President Joe Biden’s administration and the discovery of small numbers of potential noncitizens on voter rolls in some states.

Independent political analysts and democracy advocates note it is already illegal for noncitizens to vote in U.S. federal elections and say that any flagging faith in the system is the result of former President Trump’s false claims that his 2020 election loss to Biden was the result of fraud.

The proposed amendments are the latest salvo in a campaign that has included at least eight Republican lawsuits challenging voter registration processes and an attempt by the House of Representatives Republican majority to pass a law requiring Americans to provide proof of citizenship to register to vote.

Democrats and even some Republicans say the measures reflect Trump’s ongoing attempts to cast doubt on the reliability of U.S. elections.