The pro-Trump super PAC that vowed an ad campaign against Nevada Republican Sen. Dean Heller within hours of him on Friday opposing the GOP’s ObamaCare overhaul bill previewed its attack Saturday on social media.

“Why did @SenDeanHeller lie to voters about #RepealAndReplace? He’s now with @NancyPelosi. NOT GOOD! #HellerVotesYes,” tweeted America First Policies, run by former President Trump and Vice President Pence campaign staffers.

The group has bought $1 million worth of traditional ads (typically TV and radio) and is expected to start running them next week in Nevada, in addition to a digital ad campaign.

Heller is one of five GOP senators opposing the bill. The chamber has 52 GOP senators. Leaders of the GOP-controlled chamber need 51 votes to pass their ObamaCare bill. That means a maximum of two can defect, and that would require Pence to cast the deciding vote in what would be a 50-50 tie with Senate Democrats.

Heller is up for re-election in 2018 and is considered one of the most vulnerable GOP senators.

"Obamacare is collapsing. This is a crisis for the American people. There is no excuse for any Republican or Democrat to oppose the Senate health care bill outright," group President Brian Walsh said Friday. "Senator Heller ... appears to be heading down a path with Nancy Pelosi, Chuck Schumer and the radical left."

The other GOP senators who oppose the bill are Sens. Ted Cruz, Texas; Ron Johnson, Wisconsin; Mike Lee, Utah; and Rand Paul, Kentucky.

Senate Majority Leader Mitch McConnell, R-Ky., released the bill Thursday, which awaits a financial analysis by the nonpartisan Congressional Budget Office and a floor vote by as early as next week.

“This bill currently in front of the United States Senate is not the answer.” Heller said Friday. “In this form, I will not support it.”