White House senior adviser Stephen Miller had more editorial influence over the right-wing news website Breitbart during the 2016 presidential campaign than previously known and attempted to push articles attacking then-presidential candidate Sen. Marco Rubio, R-Fla., according to a new batch of leaked emails shared with NBC News.

The emails, which were first given to the Southern Poverty Law Center by former Breitbart writer Katie McHugh, reveal that Breitbart published an article in October 2015 about immigration levels with the byline “Breitbart News” under the direction of Miller while he was working for then-Senator Jeff Sessions.

The emails offer a window into just how closely Miller coordinated with Breitbart, a publication that backed President Donald Trump early in his campaign. Its former chief executive, Steve Bannon, later served as an adviser to Trump.

On Oct. 3, 2015, Miller sent a chart that claimed that “For Every 1 New Amerian Added to the Population, Immigration Will Add 7 More” to McHugh, Breitbart’s Washington political editor Matthew Boyle, and Bannon.

“Also how should we run this? Under Senator Sessions’ byline? Or under ‘Breitbart News’ byline?” Boyle asked in a reply.

Miller responded that the chart and accompanying article should be run under a Breitbart News byline, in effect disguising his involvement.

“This exclusive should provide an inescapably powerful visual and analysis designed to appeal to voters of all stripes,” Miller wrote.

It is not unusual for politicians or aides to publish opinion articles in news outlets, but those articles are usually clearly marked as coming from a particular person and are not disguised as part of the editorial operation of the news outlet.

In an emailed statement, a spokesperson for Breitbart said it is “not exactly a newsflash that political staffers pitch stories to journalists – sometimes those pitches are successful, sometimes not.”

Miller, Bannon, Boyle and Sessions did not respond to requests for comment.

The new batch of emails, released by Michael E. Hayden at the SPLC on Tuesday, also show that Miller repeatedly sent McHugh editorial guidance from his personal email address when he was working for the Trump campaign from 2015 to 2016. In one email highlighting Trump’s stances on crime, Miller implores McHugh to “make sure this is put in [the] lede,” which is a journalism term for the first paragraph of the article.

The first batch of emails, released last week, included correspondence in which Miller pointed McHugh to white nationalists websites that have been categorized as hate groups by the SPLC, including thewhite supremacist websites VDare and American Renaissance. VDare and American Renaissance repeatedly push the “great replacement” and “white genocide” conspiracy theory, which posits that a shadowy group is attempting to eliminate white majorities in the United States through immigration and encouraging mixed-race families.

Miller, who joined Trump’s campaign in early 2016 and currently works as a senior advisor in the White House, is credited as an architect and advocate for the Trump administration’s child separation policy at the U.S.-Mexico border.

More than 80 members of Congress, all Democrats, have called for Miller to resign since Miller’s emails to McHugh were first published last week. Rep. Alexandria Ocasio-Cortez, D-N.Y., first called for Miller to resign last week, attaching an online petition to her tweet. That petition now has collected over 50,000 signatures.

The new emails also show Miller repeatedly attempted to direct McHugh’s coverage about Rubio in 2015 and 2016.

“Stephen Miller is an extremist and, for some reason, he had this pathological determination to tank Rubio’s campaign,” McHugh told NBC News on Monday.

Rubio has been considered a right-leaning moderate on immigration and sought to find a bipartisan compromise on the issue as a part of the “Gang of Eight” group of senators working on the topic. His track record on the issue became fodder for attacks during his run for the 2016 Republican presidential nomination.

In December 2015, Miller sent McHugh a blog post from a local New Rochelle, New York, website about an undocumented immigrant who was arrested for allegedly raping a child.McHugh said she’d cover the story, and would “send you a link once it’s up.”

“Can you work in a reminder that Rubio’s bill — which he was pushing for Obama — legalized alien sex offenders, ensuring more such rapes would occur?” Miller wrote in one email. “[Rubio] invents facts to hurt Americans, seems to be the trend.”

In several other emails to McHugh, Miller called Rubio “pathological” and said he is “an extremist who wants unlimited immigration. The American people are moderate and want to hit pause after the deluge.”

McHugh has since disavowed her career at Breitbart and admitted she used to subscribe to white nationalist beliefs.

“Stephen Miller is a very intense and obsessive person,” McHugh said. “He’s one of those white nationalists who puts a veneer of intellectualism on things, so he was able to get away with them.”