CNN anchor Don Lemon made it clear that he thought Republican presidential candidate Nikki Haley "isn't in her prime," but he had a much different attitude toward Democratic women who sought the Oval Office. 

Lemon cited "Google" to argue Thursday that 51-year-old Haley will have an uphill battle in winning the presidency since women are only in their prime during their "20s, 30s and 40s," reacting to her comments calling for "mandatory mental competency tests" for politicians over 75 years old.

But the 56-year-old CNN host, who had just been pulled from his solo gig in primetime for a morning show shared with two co-hosts, apparently held a different standard for several female politicians who ran for president, all who were older than Haley when they ran. 

Also, all Democrats. 

CNN'S DON LEMON ROASTED AS ‘SEXIST’ FOR SAYING NIKKI HALEY IS PAST HER ‘PRIME’

Elizabeth Warren at debate

Sen. Elizabeth Warren, D-Mass., was 69 years old when she launched her presidential campaign, but CNN's Don Lemon never expressed she was not in her "prime." (AP Photo/Patrick Semansky)

When Massachusetts Sen. Elizabeth Warren announced her candidacy in February 2019 at 69 years old, Lemon did not comment on whether she was still "in her prime." Instead, his entire focus was on then-President Trump's "racist attacks" and "slurs" against Warren, who he famously referred to as "Pocahontas" for her past dubious claims to Native American heritage. 

Lemon appeared impressed with Warren's performance at a CNN town hall the following month, telling viewers she "handled herself pretty well" and "had an answer for everything," adding he didn't see anything that was going to "hurt her" on the campaign trail. 

After he himself moderated a town hall with then-58-year-old Minnesota Sen. Amy Klobuchar, Lemon declared she did "very well."

"She's warm, she's personable, but guess what – she's real. She's a truth-teller," Lemon told CNN colleague Dana Bash. "And I think from being here in New Hampshire, that's what people like about her, is that she is not fighting for the far left wing of the party… She's someone who is a liberal but also moderate on certain issues, and I don't think will take the party to the socialist side. That is my impression of it. But just the way she did tonight, I thought she did a fantastic job. She answered every single question directly, and if she didn't, then you know, I had a response to it to make sure that she answered one or two times I had to make sure that she got back on track but she did."

Lemon later hailed Klobuchar's "gumption" for telling a student on a college campus that she did not support free college and appeared to conclude that she's "strong enough" to take on President Trump in a general election.

CNN'S DON LEMON GUSHES OVER ‘REAL TRUTH-TELLER’ AMY KLOBUCHAR AFTER MODERATING TOWN HALL

Amy Klobuchar and Don Lemon at CNN town hall

Don Lemon said then-58-year-old Democratic presidential candidate Sen. Amy Klobuchar did a "fantastic job" at a CNN town hall he moderated. (Mario Tama/Getty Images)

He offered a similar response to then-California Sen. Kamala Harris, 54, following a separate CNN town hall, saying that the former prosecutor answered questions "in a very prosecutorial way," adding her comments were "very thought out" and that she was "very prepared with information and knowledge on all of the subjects that she tackled and questions she had this evening."

When then Democratic nominee Joe Biden tapped then-55-year-old Harris to be his running mate in August 2020, Lemon had an emotional message to Black women while celebrating the future VP. 

"Despite all that you do, year after year, of this country overlooking you, passing you over, not giving your due, Black women, for tonight at least, America is not taking you for granted," Lemon said. "Today is your day. And the day is historic. Joe Biden choosing Sen. Kamala Harris, a Black woman, as his running mate on the 2020 Democratic presidential ticket." 

Lemon continued, "However you feel about politics whether you're a Democrat or a Republican, however conservative, liberal, this is historic. And at least this day for this part, it should be celebrated. It's progress in this moment."

NIKKI HALEY RESPONDS TO DON LEMON'S COMMENT THAT SHE'S PAST HER ‘PRIME’: LIBERALS ‘ARE THE MOST SEXIST’

NORTH LAS VEGAS, NEVADA - MARCH 01: U.S. Sen. Kamala Harris (D-CA) speaks during a town hall meeting at Canyon Springs High School on March 1, 2019 in North Las Vegas, Nevada. Harris is campaigning for the 2020 Democratic nomination for president. (Photo by Ethan Miller/Getty Images)

Sen. Kamala Harris speaks during a town hall at Canyon Springs High School on March 1, 2019, in North Las Vegas, Nevada. (Getty Images)

Even before Hillary Clinton launched her 2016 candidacy, Lemon hyped to his viewers in June 2014 that the former secretary of State, who was 66 years old at the time and (like Haley) was no longer in office, was "in fact" running for president.

"She won't say it, but let me just say for you for the record right now that Hillary Clinton is running for president of the United States. Hillary Clinton is running for president of the United States," Lemon enthusiastically exclaimed. "The only people who don't seem to realize it are the media. Ask almost anybody else and they will tell you that they thought she was running a long time ago."

Lemon pointed to her 2014 book "Hard Choices," where she addressed how she would deal with "possible landmines" like her handling of the 2012 Benghazi terrorist attack; how she kept sitting down for interviews with prominent female journalists, noting that women are a "key voting block," as well as her countless paid speeches she had given ever since she left office so she "gets to test and hone her voice for the campaign stomp."

"We won't play semantic games with you. We're gonna assume like just about everybody else out there that Hillary Clinton is, in fact, running," Lemon added. 

NIKKI HALEY CALLS FOR POLITICIANS OVER 75 TO FACE 'MENTAL COMPETENCY TESTS'

Don Lemon hypes Hillary Clinton

In June 2014, CNN's Don Lemon offered an enthusiastic rant insisting Hillary Clinton, who was 66 at the time, was running for president. (Screenshot/CNN)

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The CNN host faced intense backlash following his remarks about Haley with critics accusing him of sexism. 

Lemon tweeted out a mea culpa, writing, "The reference I made to a woman’s ‘prime’ this morning was inartful and irrelevant, as colleagues and loved ones have pointed out, and I regret it. A woman’s age doesn't define her either personally or professionally. I have countless women in my life who prove that every day."