Hillary Clinton says she believes that the Republicans have "got their eye on somebody who's currently in the Democratic primary and are grooming her to be the third-party candidate."

In a recent interview, Clinton didn't mention Democratic presidential candidate Rep. Tulsi Gabbard of Hawaii by name, but said she believes one candidate is "the favorite of the Russians." Asked if the former secretary of state was referring to Gabbard, Clinton spokesman Nick Merrill said, "If the nesting doll fits..." He later tweeted that Clinton was referring to the GOP grooming Gabbard, not Russians.

Gabbard responded with a furious tweetstorm Friday afternoon, where she blasted Clinton as "the queen of warmongers, embodiment of corruption, and personification of the rot that sickened the Democratic Party for so long."

Great! Thank you @HillaryClinton. You, the queen of warmongers, embodiment of corruption, and personification of the rot that has sickened the Democratic Party for so long, have finally come out from behind the curtain. From the day I announced my candidacy, there has been a ... — Tulsi Gabbard (@TulsiGabbard) October 18, 2019

"From the day I announced my candidacy, there has been a concerted campaign to destroy my reputation. We wondered who was behind it and why. Now we know — it was always you, through your proxies and powerful allies in the corporate media and war machine, afraid of the threat I pose," she added in subsequent tweets, challenging the 2016 Democratic nominee to enter the 2020 race.

"It is now clear that this primary is between you and me. Don't cowardly hide behind your proxies. Join the race directly," the congresswoman tweeted.

Merrill responded within minutes, saying, "Divisive language filled with vitriol and conspiracy theories? Can’t imagine a better proof point than this."

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Gabbard told NBC News Friday night in an interview in Iowa City, Iowa, that Clinton had "blood on her hands" for her support of American military action, and said the former first lady is accusing her and others who are against "regime change wars" of being "traitors and foreign agents." She said Clinton was lashing out because "it's clear to her that she can't control me."

"If I'm elected president," Gabbard said, Clinton "won't be able to manipulate me."

During a podcast appearance on "Campaign HQ" with David Plouffe earlier in the week, Clinton said the unnamed Democratic candidate was "the favorite of the Russians." "And that's assuming Jill Stein will give it up, which she might not because she's also a Russian asset. She's a Russian asset! I mean, totally. They know they can't win without a third-party candidate," Clinton said.

The Mueller report and congressional investigations have shown that Russia's interference in the 2016 election included bolstering Green Party candidate Stein's third-party run.

Stein responded to Clinton's comments on Twitter, saying, "It's a shame HRC is peddling conspiracy theories to justify her failure instead of reflecting on real reasons Dems lost in 2016."

Gabbard, who has defended Syrian dictator Bashar al-Assad, an ally of Russian President Vladimir Putin, said she has no plans for a third-party run. After Gabbard's Friday tweetstorm, Merrill tweeted at her that it was "Assad day for your candidacy."

Assad day for your candidacy. https://t.co/JsQHnY6Ygo — Nick Merrill (@NickMerrill) October 18, 2019

Some Democrats and critics have called Gabbard a Russian asset, which she blasted as "completely despicable" at this week's debate.

Merrill said Clinton's comments are not "some outlandish claim. This is reality. If the Russian propaganda machine, both their state media and their bot and troll operations, is backing a candidate aligned with their interests, that is just a reality, it is not speculation."

An NBC News analysis in February showed Russian news sites and social media linked to the Kremlin were promoting Gabbard's candidacy in the run-up to her campaign announcement. That activity has continued in the months since, The New York Times reported this week.

Gabbard, who resigned as Democratic National Committee vice chair to endorse Bernie Sanders' presidential run in 2016, took some digs at Clinton in Tuesday's Democratic presidential primary debate in Ohio.

"I agree with Hillary Clinton on one thing, disagree with her on many others," Gabbard said at one point. She also referred to Clinton's line about President Donald Trump being supported by a "basket of deplorables," saying: "When I look at our country, I don't see deplorables. I see fellow Americans, people who I treat with respect, even when we disagree and when we disagree strongly."

CORRECTION (Oct. 24, 2019: 11:50 a.m. ET): An earlier version of this article mischaracterized Clinton's remark about a Democratic candidate being groomed to be a third-party candidate, an apparent reference to Gabbard. A close reading of Clinton's remark indicates that she was referring to Republicans as doing the grooming, not Russians. This interpretation was confirmed by a Clinton aide. The article and the headline have been changed to reflect this interpretation.