Senate Majority Leader Mitch McConnell defended President Donald Trump on Tuesday, saying he "is not a racist."

This comes amid a rising tide of criticism over a tweet in which the president told four Democratic congresswomen to “go back" to their ancestors' countries.

McConnell, the senior senator from Kentucky, said everyone across the political spectrum should raise their decorum.

"It's about time we lowered the temperature all across the board," McConnell said during a Tuesday press conference in Washington. "All of us ought to contribute to a better level of discourse."

Trump's critics have been in overdrive, blasting the president's latest round of tweets in which he appeared to be targeting outspoken minority Democratic Reps. Alexandria Ocasio-Cortez of New York; Ilhan Omar of Minnesota; Ayanna Pressley of Massachusetts; and Rashida Tlaib of Michigan. All but Omar were born in the United States.

"Why don’t they go back and help fix the totally broken and crime infested places from which they came," Trump said in a tweet Sunday.

Democrats have charged that the president's tweets were racist, and Speaker Nancy Pelosi, who has squabbled with the group of congresswomen known as "The Squad," supported a resolution in the House to condemn Trump. The resolution passed largely along party lines on Tuesday night.

Background:Trump tells congresswomen to 'go back' from where they came from

"The president is not a racist," McConnell said after being pressed by reporters.

McConnell, who is running for reelection in 2020, offered little criticism of Trump, who remains a popular figure in the Bluegrass State.

That's in contrast to how the Kentucky Republican has responded in the past when his wife, U.S. Transportation Secretary Elaine Chao, has been a target because of her Asian heritage or for being an immigrant.

In those cases, McConnell has called attacks aimed at his wife racist, whether from liberal critics or from members of his own state party.

McConnell ripped a Kentucky Republican who was running for the state legislature last year, for instance, after the candidate criticized his interracial marriage during an appearance on a white nationalist YouTube show.

The candidate said at the time that white people "should maintain our people and our culture as much as anyone else" but added that McConnell’s marriage to Chao was one of "companionship" more than "a statement about children."

McConnell told the Courier Journal in a September 2018 statement that such views ran afoul of American values.

“This racist behavior is completely despicable," he said. "Such backwards views and hateful rhetoric must be given no corner in the Republican Party or anywhere in America. I’m not at all surprised that the state party is not affiliated with or in any way supporting this individual.”

Related:Kentucky GOP mostly silent in the face of Trump's racist 'go back' tweet

In 2013, McConnell also did not hold back when a liberal super PAC mentioned his wife's Asian heritage in a series of tweets. The group, Progress Kentucky, said Chao had McConnell's ear and mentioned she was his wife.

"May explain why your job moved to China," the group tweeted.

McConnell called those tweets both "racial slurs" and "the ultimate outrage" at a Republican dinner in 2013.

"Elaine Chao is just as much an American as any of the rest of them," McConnell said at the time. "In fact, she had to go through a lot more to become an American."

In 2001, McConnell accused the Courier Journal editorial board of "subtle racism" and having a case of "yellow fever" for questioning Chinese influence over his office. He said that the newspaper was engaging in a "racially tinged campaign" and had betrayed former publisher Barry Bingham Sr.'s values as a champion of racial and ethnic equality.

McConnell went as far as citing statistics from the Anti-Defamation League that said 68% of Americans have very negatives views of Chinese Americans.

"These negative views are even higher in the South, where the C-J wields its influence," he said in a 2001 op-ed.

A key part of McConnell's 2020 campaign strategy will be reminding voters about his close working relationship with Trump. Since January 2017, McConnell and the president have successfully appointed dozens of conservative judges to the federal bench, including two justices to the Supreme Court.

Trump holds a 55% approval rating in Kentucky, according to polling, which outpaces McConnell's popularity.

McConnell avoided any direct criticism of the president's tweets on Tuesday, and instead focused on the four congresswoman and their past comments. He called out "The Squad" for regularly criticizing U.S. policies, such as immigration at the southern border and the country's relationship with Israel.

"We’ve heard facilities on the U.S. border called 'concentration camps,' we’ve seen the far left throw accusations of racism at everyone — anyone who disagrees with them on anything, including the speaker of the House," McConnell said.

"We’ve seen a freshman Democratic congresswoman use anti-Semitic tropes and imply people only support Israel because of campaign contributions. The most vile accusations and insults against our nation have become incredibly routine, and we’ve seen back and forth over the past few days."

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McConnell was questioned by reporters on Tuesday about how he would respond to someone saying Chao should return to her native country of China if she criticized federal policy.

"Wouldn't you consider that a racist attack?" a reporter asked.

McConnell responded with a brief explanation of Chao's biography as an 8-year-old girl who came to the U.S. legally without knowing how to speak English. He then talked about the virtues of immigration, but did not address whether Trump's assertion for the congresswomen to "go back" to their countries was racist.

"Legal immigration has been a fulfilling of the American dream; new people who come here have a lot of ambition, a lot of energy and tend to do very well and invigorate our country, and my wife is a good example of that," McConnell said.

Reporter Phillip M. Bailey can be reached at 502-582-4475 or pbailey@courierjournal.com. Support strong local journalism by subscribing today: courier-journal.com/philb.