"But they didn't vet people to see who they really are. Anybody can go in there and say, 'I am Joe Smith, I want an ID card.' It's absurd. There is a lot of fraud. Not just voter fraud, all kinds of fraud. This is why I get more conservative as I get older."
Breaking with the Democratic party position, Mr Schulkin said he backed laws requiring voters to produce photo ID when voting. In the US, voter ID laws exist in two thirds of states but are highly controversial, split down party lines, and in some cases subject to court challenges.
Conservatives believe voter ID laws are required to stamp out vote fraud. Liberals and civil rights groups counter that vote fraud is practically non-existent, arguing voter ID laws discriminate against minorities and poor people.
In comments which have been seized upon by conservatives in the US, Mr Schulkin said he didn't think it was "too much to ask somebody to show some kind of an ID".
"You go into a building, you have to show them your ID," he said.
"The law says you can't ask for anything. Which they really should be able to do. I believe they should be able to do it. They should ask for your ID. I think there is a lot of voter fraud."
Contacted by the New York Post on Monday, Mr Schulkin defended his remarks but reiterated his support for voter ID. "I should have said 'potential fraud' instead of 'fraud'," he said.
In Australia, voters aren't required to produce an ID card at the polling place, but compulsory voting lessens the impact of any potential fraud.
In 2001, Labor MP Michael Danby made the point that during the previous 10 years, the AEC had conducted "six electoral events, including four elections, a Constitutional Convention and a referendum". Out of 72 million votes cast, there were 72 cases of proven electoral fraud.
But in the US, where only about 60 per cent of the eligible population votes during presidential elections, fears of fraud are much more pronounced. Vote fraud can include casting multiple votes, voting by non-citizens, and voting by the deceased.
Last month, The Washington Post reported the FBI and police were investigating how at least 19 dead Virginians, including a local World War II veteran, were registered to vote. A university student, working for a Democrat-aligned voter registration group, later confessed.
"Oftentimes we hear our Democratic colleagues suggest that voter fraud doesn't exist in Virginia, or it's a myth," Republican politician William J. Howell said.
"This is proof that voter fraud not only exists but is ongoing and is a threat to the integrity of our elections."
Democratic politician David J. Toscano countered that the case was not proof of voter fraud because no one had managed to cast a vote in the names of the dead.
"First of all, there was no voter fraud - they caught him," he said. "Nobody cast a vote. There's still no evidence of that going on in the state. But there is evidence every time you turn around that the Republicans are trying to make it more difficult for citizens to vote in elections."
The other big concern for conservatives is voting by America's estimated 11 million illegal - sometimes referred to as "undocumented" - immigrants.
According to a 2014 study by researchers from Old Dominion University, analysing data from the Cooperative Congressional Election Study, more than 14 per cent of non-citizens in both 2008 and 2010 indicated they were registered to vote.
The researchers estimated that 6.4 per cent of non-citizens voted in 2008 and 2.2 per cent of non-citizens voted in 2010. If true, that would account for an estimated 700,000 additional votes cast in 2008.
"Most non-citizens do not register, let alone vote. But enough do that their participation can change the outcome of close races," the researchers wrote.
"Because non-citizens tended to favour Democrats (Obama won more than 80 per cent of the votes of non-citizens in the 2008 CCES sample), we find that this participation was large enough to plausibly account for Democratic victories in a few close elections."
And in the case of multiple voting, a 2012 study by the Pew Center on The States found approximately 2.75 million people had registrations in more than one state, while 68,000 were registered in three states.
Last month, a 63-year-old Tennessee man was charged with voting not once, but three times, in three different states, in the 2012 presidential election, Fox News reported. The case was one of nearly 150 turned over to authorities for investigation by watchdog group The Voting Integrity Project.
"It's a lot more widespread than what people think, because the general public thinks there is no voter fraud," the group's executive director Jay DeLancy told Fox News. "As proof they look at prosecutions, but we have learned how difficult it is to get prosecutions."
For the record, here are the arguments for and against voter ID as they broadly stand. On the against side, the American Civil Liberties Union. On the for side, conservative think tank The Heritage Foundation.
The ACLU describes voter ID requirements as "a solution in search of a problem". "There is no credible evidence that in-person impersonation voter fraud - the only type of fraud that photo IDs could prevent - is even a minor problem," the group says.
"Proponents of voter ID laws have failed to demonstrate that individual, in-person voter fraud is even a minor problem anywhere in the country.
"Requiring voters to obtain an ID in order to vote is tantamount to a poll tax. Although some states issue IDs for free, the birth certificates, passports, or other documents required to obtain a government-issued ID cost money, and many Americans simply cannot afford to pay for them."
The Heritage Foundation, meanwhile, describes them as "essential to fair and free elections". "Think of all the other activities - many of them far less impactful than voting - that require you to show identification," the group says.
"Getting a library card, buying a beer, picking up baseball tickets at will call, applying for food stamps, renting a car, obtaining a fishing license, purchasing NyQuil - the list goes on and on.
"We whip out an ID for daily entertainment and responsibilities without giving it a second thought. Surely we can expect to do so for such an important action as electing the president of our country and leader of the free world."
