CNN's KFile team reported
in early December that Murray, whom Trump nominated in May to be the alternate representative for special political affairs to the United Nations, praised far-right provocateur Milo Yiannopoulos and shared disparaging memes about prominent Democrats and progressives on social media.
Murray's nomination was approved by the Senate Foreign Relations Committee in August but he was never voted on by the full Senate. If confirmed, Murray would serve under Ambassador Nikki Haley in representing US interests at the United Nations and would act as a fill-in for Haley in representing the US to the United Nations General Assembly when she is unavailable.
Nominees who are not confirmed by the end of the Senate session must receive unanimous approval from the chamber to be carried over for consideration in the next session. Any one senator can object to carrying them forward. Nominations not approved are returned to the White House and those nominees must then be re-nominated if they are to proceed.
Murray's nomination was not held over to the next session, according to a full list of nominees
sent back to the White House released by the Senate on Tuesday.
Hogan Gidley, a White House spokesperson, declined to say specifically if Murray would be re-nominated.
"This is a standard paperwork practice due to long-established Senate rules, and we will proceed as necessary with re-nominations in January," Gidley wrote in an email.
Murray did not respond to a request for comment.
Senate Democrats last year launched challenges to several of Trump's nominees who they viewed as unqualified. In a joint news conference with Majority Leader Mitch McConnell in October, Trump said Democrats were obstructing his nominations, calling their actions "unfair."
Among the other nominees sent back to the White House are Alex Azar, Trump's nominee to lead the Department of Health and Human Services and K.T. McFarland, the former deputy national security adviser whose nomination to be ambassador to Singapore came under scrutiny over her communications with former national security adviser Michael Flynn.