What is voter fraud? The types of election interference White House could investigate

President Trump on Wednesday announced his intention to seek a "major" investigation into American voter fraud -- something the new commander in chief has claimed lost him millions of votes.

As the White House doubles down on Trump's claim that millions of people interfered in the November election, many are unsure what actually, legally constitutes as "voter fraud."

According to Ballotpedia, any illegal interference with the process of an election constitutes as "voter fraud."

These are the different types of voter fraud they list:

Double voting (ballot stuffing): One individual casts more than one ballot in the same election.

Dead voters: The name of a deceased person remains on a state's official list of registered voters and a living person fraudulently casts a ballot in that name.

Felon voter fraud: The casting of a ballot by a convicted felon who is not eligible to vote as a result of being a felon.

Voter suppression: A variety of tactics aimed at lowering or suppressing the number of voters who might otherwise vote in a particular election.

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Registration fraud: Filling out and submitting a voter registration card for a fictional person, or filling out a voter registration card with the name of a real person, but without that person's consent, and forging his or her signature on the card.

Voter impersonation: A person claims to be someone else when casting a vote.

Vote-buying: Agreements between voters and others to buy and sell votes, such as a candidate paying voters to vote for him or her.

Fraud by election officials: Manipulation of ballots by officials administering the election, such as tossing out ballots or casting ballots in voters' names.

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Widespread voter fraud would have serious implications for the state of American democracy, and worry about different modes of election interference have historically been split along party lines. As evidenced in Trump's claim, Republicans are historically more worried about registration fraud and double voting, while Democrats often advocate for an end of voter suppression -- which has been a longstanding issue in U.S. areas with minority voters.

President Obama addressed claims of widespread voter fraud in the final White House press conference -- deeming it "fake news."

"We are the only country in the advanced world that makes it harder to vote rather than easy," said President Obama. "Make it easier, not harder."

Sen. Bernie Sanders echoed the former president's statement on Wednesday, when he described vote suppression as "the great political crisis."

While there are some federal statutes that govern voting -- like the Civil Rights Acts of 1971 and 1974 that there were passed as protections against discrimination in voting -- many voting regulations are implemented at the state level. At the state level, there are many differences in processes relative to absentee ballots, early voting, day-of voting and registration deadlines. These processes are overseen by secretaries of state.

The National Association of Secretaries of State on Tuesday said there was no evidence of Trump's claims in the 2016 election.

"We are not aware of any evidence that supports the voter fraud claims made by President Trump," the group of state elections officials said Tuesday in a statement. "In the lead up to the November 2016 election, secretaries of state expressed their confidence in the systemic integrity of our election process as a bipartisan group, and they stand behind that statement today."

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