The Justice Department sent out more than 20 target and preservation letters as part of its investigation into Daniel J. Sullivan’s campaign for U.S. Senate in Alaska, two sources familiar with the investigation told Fox News Digital.

President Donald Trump's DOJ launched in July its investigation into the retired schoolteacher suspected of being recruited as a spoiler candidate in the race against Sen. Dan Sullivan, R-Alaska, earning him the nickname "Decoy Dan." A source familiar with the investigation said more than 120 subpoenas have been issued since the probe began this summer. The investigation initially focused on whether Daniel J. Sullivan’s candidacy was intended to confuse voters and undermine the fairness of the election.

"This is a situation where everybody agrees that there is a FRAUD on the ballot," Attorney General Todd Blanche told Fox News Digital. "Everybody agrees that there is a man running that doesn't want to run, that doesn't expect to be senator, that is only running to confuse Alaskan voters." Last Thursday, the Trump administration issued more than 30 subpoenas in a 24-hour period following a New York Times report detailing alleged coordination between the Democratic Senatorial Campaign Committee, Democratic operatives and people connected to Mary Peltola’s campaign to recruit Sullivan, a source familiar told Fox News Digital.

The New York Times first reported on Election Day that the Justice Department had issued the letter notifying individuals that they were under investigation and letters notifying individuals to preserve their communications and documentations.

The report named Marc Elias, an election lawyer whose firm Elias Law Group has represented Peltola, and an official from the Democratic Senatorial Campaign Committee, as recipients of those notices. It is not clear who else has received comment preservation or target letters.

President Trump has been highly critical of the alleged efforts of the Democratic Party to siphon voters away from Sen. Sullivan.

His administration previously filed a lawsuit against Alaska officials to prevent them from certifying election results if it was deemed Daniel J. Sullivan may have cost Sen. Sullivan the election. That that lawsuit was tossed out by a federal judge Sunday.

"You had the Democrat Party headed up by Elias, their lawyer, who was a bad guy, very bad guy — should go to jail, in my opinion," Trump shared on "Fox & Friends Tuesday." "But you had the Democrat Party look all over Alaska for somebody named Sullivan." Trump also suggested that Senate Minority Leader Chuck Schumer should be held "criminally responsible," as well.

Sources familiar with the investigation shared with Fox News Digital that the letters were not sent exclusively to Democratic officials, but they would not give more information or provide specifics about who the recipients were or how many received target versus preservation letters. The letters were not sent out on Election Day.

Alaska Republican Gov. Mike Dunleavy argued this the state's nonpartisan primary system is to blame for allowing Daniel J. Sullivan to advance to the general election. Under Alaskan's election system, the top four finishers regardless of their party will advance. Daniel J. Sullivan did not run under any political party.

"If this was a historical primary, a primary that our fathers and grandfathers had, this individual [retired schoolteacher Dan Sullivan of Petersburg] would not have gotten out of the primary," Dunleavy told Fox News Digital.

The heightened focus in the Alaskan Senate race comes after the New York Times investigation last week, which followed with Alaska U.S. Attorney Michael Heyman officially announcing at a news conference Friday the investigation into Daniel J. Sullivan's campaign. Heyman did not say at the news conference what criminal charges are being pursued.

"I'm not making any assumptions on whether a crime has been committed or not," Heyman said. "That's why we are conducting that thorough investigation." The Justice Department declined to comment on the ongoing investigation when reached by Fox News Digital.