Tense conversations between members of Senate Majority Leader Mitch McConnell’s political team and allies of President Donald Trump may have forestalled a big television attack planned against Sen. Dean Heller, one of the chamber’s most vulnerable Republicans.

Heller last week came out against the Senate version of a health care bill designed to repeal Obamacare. Soon after, officials at America First Policies said they would target the Nevadan in a negative seven-figure blitz that would begin on social media and spread to TV.

The nonprofit group is run by key Trump campaign operatives, including top digital advertising strategist Brad Parscale. Within hours Parscale had created a series of provocative tweets and a video tying Heller to Nancy Pelosi, the House Democratic leader whom Republicans used to winning effect as a political bogeyman in the recent special election in Georgia. While evidence of purchased TV time in Nevada has not materialized, the moves earned a great deal of free media attention, and the shot across the bow could not have been clearer.

The tactics have alarmed many in the GOP. Heller is up for reelection next year in a state where Hillary Clinton beat Trump. He’s a top target for Democrats — why should he also be a top target for friends of the Republican president?

McConnell was not given a heads-up that the anti-Heller campaign was coming — and he was not happy about it, according to several Republican sources.

One source familiar with subsequent talks between the McConnell and America First camps told BuzzFeed News that McConnell’s side directly voiced its displeasure. And the McConnell allies, tasked with maintaining GOP control of the Senate in next year’s midterm elections, came away from the talks convinced that America First would not go with the overly harsh TV ads initially telegraphed.

“I think assurances would be the wrong word,” said the source, who requested anonymity to share details of private conversations. “They have at least given the impression that they understand [McConnell’s frustrations] and that they will pull back.”

America First might continue its social media blasts against Heller, the source added. (As of Monday evening, one tweet linking Heller and Pelosi was pinned atop of the group’s Twitter page.) But attack ads on Nevada airwaves are believed to be off-limits.

A spokeswoman and other officials with America First did not respond to questions about the discussions with McConnell’s team. Earlier Monday, the spokeswoman disputed an Associated Press report that the group was expanding its campaign to include other Republican senators who have concerns with the health care bill. America First has been making phone calls to voters in states represented by fence-sitting Republicans, offering words of encouragement for the bill. And in the spring the group aired ads meant to encourage Republican House members who were seen as swing votes on health care.

America First also is targeting Democratic senators with cable TV buys in Indiana, Michigan, Missouri, Montana, North Dakota, Ohio, Virginia, and West Virginia.

“These are state-specific ads that encourage constituents to ‘call their senator’ and tell them to replace Obamacare,” said the America First spokeswoman, Erin Montgomery.

Axios reported Monday that America First could go the kinder encouragement route with Heller, provided he signals an openness to voting for the final bill. One operative who works closely with America First told BuzzFeed News that story should not be interpreted as retreat.

“It talks about optionality in content — not a debate of doing it or not doing it,” the operative said.