Major League Baseball is requesting the return of its $5,000 donation to Sen. Cindy Hyde-Smith’s campaign, in the latest blow to the Mississippi Republican ahead of Tuesday’s runoff.

MLB spokesman Pat Courtney said in a statement that the donation “was made in connection with an event that MLB lobbyists were asked to attend” and that MLB has requested that it be returned.

Melissa Scallan, a spokeswoman for Hyde-Smith’s campaign, said she could not comment on the matter.

News of the donation was first reported Saturday by the political newsletter Popular Information.

Hyde-Smith, who was appointed to the Senate in the spring, faces Democrat Mike Espy in Tuesday’s runoff to fill the remaining two years of the term to which retired Republican Thad Cochran was elected.

Hyde-Smith’s victory in the runoff was once considered a foregone conclusion, but her campaign has been roiled in recent weeks by revelations that she made a controversial allusion to lynching and embraced Confederate history at several points throughout her career.

President Trump has thrown his support behind Hyde-Smith and is making two stops in the state on Monday to campaign on her behalf.

“I will be in Gulfport and Tupelo, Mississippi, on Monday night doing two Rallies for Senator Hyde-Smith, who has a very important Election on Tuesday,” Trump tweeted Sunday morning. “She is an outstanding person who is strong on the Border, Crime, Military, our great Vets, Healthcare & the 2nd A. Needed in D.C.”

Earlier this month, a video posted to Twitter by journalist and blogger Lamar White Jr. showed Hyde-Smith saying of a supporter during a campaign stop, “If he invited me to a public hanging, I’d be on the front row.”

Hyde-Smith first defended the statement as an “exaggerated expression of regard” for the supporter before offering a limited apology during a debate with Espy last week.

Days later, another video showed Hyde-Smith apparently joking about voter suppression, saying laws that “make it just a little more difficult” for some college students to vote are “a great idea.”

Espy, who would become the first black senator to represent Mississippi since the Reconstruction era if elected, has called Hyde-Smith’s comments on public hangings “reprehensible” and said they had “given our state another black eye that we don’t need.” Rep. Bennie Thompson (D-Miss.) also blasted the remarks, noting that Mississippi had among the highest numbers of public lynchings of any state in the country.

News of the comments prompted a backlash against Hyde-Smith from several corporate supporters, including Walmart, which asked for its donations to be returned and said in a tweet last week that the senator’s remarks “clearly do not reflect the values of our company and associates.”

AT&T, Leidos, Union Pacific and Boston Scientific also have asked for their contributions to be refunded, CNBC reported.

Charles B. Johnson, the majority owner of the San Francisco Giants, also has come under fire after the San Francisco Chronicle reported that he and his wife contributed the maximum $2,700 to Hyde-Smith’s campaign.

Marcos Breton, a columnist for the Sacramento Bee, wrote Saturday that he was no longer supporting the Giants in the wake of the news.

“I am hereby financially boycotting the team of my youth,” Breton wrote, calling Johnson “an enabler of a bigot who has espoused support for voter suppression. He has given his money to a candidate who makes jokes about public lynchings, and I can’t support that.”

A report Friday by the Jackson Free Press that Hyde-Smith attended an all-white segregation academy in the 1970s prompted further scrutiny of the senator’s background.

Scallan did not dispute the report but dismissed it in a statement, arguing that “the gotcha liberal media has taken leave of their senses.”

“They have stooped to a new low, attacking her entire family and trying to destroy her personally instead of focusing on the clear differences on the issues between Cindy Hyde-Smith and her far-left opponent,” the spokeswoman said.