After Donald President Trump made an unfounded claim that massive voter fraud perpetrated by Massachusetts residents kept him from beating Hillary Clinton in New Hampshire last November, Gov. Charlie Baker said Monday there are ways to investigate such claims.

Several outlets reported last week that Trump told a group of U.S. Senators that he and former Sen. Kelly Ayotte lost in the Granite State because thousands of people were bused from Massachusetts to illegally vote in the New Hampshire.

Baker's office wouldn't comment on whether he supports an investigation by the federal government or anyone else. He told reporters he doesn't know enough about the situation.

"I don't know much about what goes on in New Hampshire, so I'm really not really in a position to speak to that one. Obviously, people have concerns up there. I'm sure there's a process for redress that you pursue to determine if in fact there were any issues," Baker.

Senior White House adviser Stephen Miller repeated Trump's claims Sunday morning in an interview with ABC's George Stephanopoulos, calling the issue "very, very serious."

“I can tell you that this issue of busing voters into New Hampshire is widely known by anyone who’s worked in New Hampshire politics,” Miller said.

Federal Election Commissioner Ellen Weintraub said in a statement Friday that "allegations of this magnitude cannot be ignored," and called on Trump to share his evidence of the fraud with law enforcement officials. According to Weintraub, voter fraud on the scale Trump claims could result in thousands of felony charges under New Hampshire law. The White House has provided no evidence that any Massachusetts residents voted illegally in New Hampshire.

Trump reportedly said New Hampshire's same-day voter registration rules lead to the thousands of fraudulent votes. Baker says he doesn't support a similar same-day system in Massachusetts because of the burden it would put in smaller communities.

"As a general rule, I don't support same-day voter registration because I think it's a really difficult task for a lot of our smaller communities to manage," Baker said.

Baker praised Massachusetts's own early-voting system, saying he was impressed by how many voters took advantage of the extended voting time last year.