Several conservative groups are echoing President Trump's call to repeal Obamacare first and then work on a replacement, which would be a dramatic shift from Congress' current approach.

Conservatives cheered a tweet by Trump on Friday morning that if the Senate can't pass healthcare reform, it should repeal Obamacare now and create a replacement later. Sens. Rand Paul, R-Ky., and Ben Sasse, R-Neb., also called for repeal and delay.

"It's good to see the president joining us in terms of full repeal effort at this stage," said Ken Cuccinelli, the president of the Senate Conservative Fund PAC, on a call with several groups Friday.

Conservatives expressed frustration with the Senate's healthcare reform bill that they say does little to repeal Obamacare, which Republican leaders promised to fully scrap.

"The only way to get this done now is to repeal first, come back and begin to improve our current system," said former Sen. Jim DeMint, who recently was removed as president of the conservative Heritage Foundation think tank.

Senate Republicans left town Thursday without a health deal. Majority Leader Mitch McConnell scrapped a planned vote this week because the bill didn't have enough support.

Conservative groups blasted the bill as keeping too much of Obamacare, a key criticism from conservative senators as well.

"This is an amendment to Obamacare," said Jason Pye, director of public policy for the Koch-backed FreedomWorks, which on Friday backed repeal and delay.

Pye went after Senate moderates who have been pushing McConnell for more money to fight opioid abuse and change Medicaid. He noted that in 2015 several of those senators voted for full repeal, which would have left Obamacare in place for a few years while a replacement was crafted and passed.

"These so-called moderates in the Senate have to find whatever shreds of conservatism they have left in their souls to get this done and get this done quickly," he said.

Andy Roth of the Club for Growth said he wants a repeal bill to be put up for a vote and dared moderates to vote against it.

"The entire problem with the House bill and the Senate bill is that full repeal was never considered," he said. "Moderate Republicans have fundamentally lied to the voters about their true positions."

Roth also advocated a repeal and delay strategy for Obamacare, but said that any repeal bill needed to fully gut the law's regulations.

"We do not want to do partial repeal now, leave the regulations in place and allow moderates and Democrats to conspire to pass a replacement," he said.

But it is not clear if the Senate leaders will scrap the bill they announced last week and move toward a repeal and delay strategy.

Pye said that if leadership doesn't adopt repeal and delay, then it at least needs to adopt an amendment from Sen. Ted Cruz, R-Texas, that would let insurers sell plans that don't comply with Obamacare's insurance mandates as long as they sell some plans that do.

McConnell is reportedly weighing the amendment.