Senate Republicans unveiled a "discussion draft" of the bill Thursday of their plan to repeal and replace Obamacare that would end the health care law's penalties for people who don't buy insurance, cut back an expansion of Medicaid, but would keep protections for people with pre-existing conditions, compared to the House-passed bill.

Here's the full text of the "discussion draft" of the bill.

The 142-page measure would provide tax credits, based on income, age and geography, which would make more money available to lower income recipients to help them buy insurance. This differs from the House bill, which tied its tax credits to age. Obamacare taxes would be repealed under the bill. The Senate bill would provide for expanded tax-free Health Savings Accounts, and it would also eliminate federal funding for Planned Parenthood.

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Medicaid would be phased out under the bill beginning in 2021, with gradual reductions until 2024 in the amount of federal Obamacare funds that have financed the entitlement program's expansion. The Senate bill would also slash funding to Medicaid from what Republicans call "gimmicks that drive up federal costs." President Trump repeatedly promised during the 2016 presidential campaign that he would not cut Medicaid, Medicare or Social Security.

Senate Majority Mitch McConnell, R-Kentucky, aims to hold a vote on the legislation before lawmakers leave at the end of next week for the week-long July 4 recess.

"Obamacare isn't working. By nearly any measure, it has failed, and no amount of 11th-hour, reality-denying or buck-passing by Democrats is going to change the fact that more Americans are going to get hurt unless we do something," he said on the floor after the bill was posted. "Republicans believe we have a responsibility to act, and we are."

Senate Minority Leader Chuck Schumer, D-New York, noted that the president had asked for a bill with more "heart" than the House bill, but this bill, Schumer said, is "every bit as bad" as the House version and maybe "meaner." "The way this bill cuts health care is heartless," he said on the floor.

"This bill will result in higher costs, less care and millions of Americans will lose their health insurance, particularly through Medicaid," Schumer added.

Republicans need a simple majority to pass it, rather than a supermajority since they're using the budget reconciliation process. They may still have to rely on Vice President Mike Pence to cast a tie-breaking vote. The Senate currently has 52 Republicans and 48 Democrats. That means if all Democrats vote against the bill, only three no votes from Republicans can torpedo it. Even if Republicans are successful in getting it through the upper chamber, they would then still need to reconcile it with version passed by the House in early May, reach a bicameral agreement with House Republicans, and hold votes in the House and Senate on that version again.

A cost estimate of the bill from the nonpartisan Congressional Budget Office (CBO) is expected to be released by early next week. White House staff met with Senate Republican staffers Wednesday night on Capitol Hill to review the bill.

On Thursday morning, the Senate Republican Conference sat through a closed-door briefing for an hour and a half to learn about the bill's substance. Many inside the meeting didn't actually see the text even though it was posted online.

"You've seen the text?" Moderate Sen. Lisa Murkowski, R-Alaska, asked a reporter. "Well, you've seen it before we've seen it."

Sen. John McCain, R-Arizona, called it a "good proposal overall," but that there's "a lot to absorb."

Senators who emerged from the meeting didn't appear entirely confident it would pass next week.

"I think we have a long way to go before we know the answer to that question, Sen. Tim Scott, R-South Carolina, said when asked if it could pass next week, adding that the draft version could be modified before a vote happens. "I'm open to moving forward on the legislation. We have a lot of time now -- seven days -- to figure out what parts we like about it, what parts we plan to keep. This is only a draft legislation. We're going to make a lot of changes over the next seven days.

Several senators are already expressing concerns about the proposal.

"At first glance, I have serious concerns about the bill's impact on the Nevadans who depend on Medicaid. I will read it, share it with Governor Sandoval, and continue to listen to Nevadans to determine the bill's impact on our state," said Sen. Dean Heller, R-Nevada, in a statement. Heller is up for re-election next year and is considered by Democrats to be one of the most vulnerable Republicans.

Sen. Rand Paul, R-Kentucky, didn't appear to be a fan of the bill.

"Conservatives have always been for repealing Obamacare, and my concern is that this doesn't repeal Obamacare," Paul told reporters. "What I've seen so far is that it keeps 10 out of 12 regulations, it continues the Obamacare subsidies, and I think ultimately will not bring down premiums, because instead of trying to fix the death spiral of Obamacare, it simply subsidizes it with taxpayer money to insurance companies. So for those reasons, it looks a lot like Obamacare instead of a repeal of Obamacare."

Sen. Bill Cassidy, R-Louisiana, said he's happy that the bill makes an effort to lower premiums "immediately," but he said he wants to ensure that as Medicaid is scaled back, "We don't lose the the ability for lower-income folks to be able to afford insurance."

Sen. Lindsey Graham, R-South Carolina, said in a statement that he needs to carefully review the text first, but "would prefer to address health care reform in a bipartisan manner," accusing Democrats of being unwilling to negotiate with Republicans.

The House bill, which narrowly passed in a 217-213 vote on May 4, would significantly reduce the funding for Obamacare subsidies, revamp tax credits so that they're tied to a person's age, freeze the Medicaid expansion in 2020 and allow states to seek waivers from a rule that requires states to offer essential benefits in their plans and a provision that prevents insurers from charging people with pre-existing conditions more money compared to healthy people. Instead of Obamacare's insurance mandate, the House Republican bill would incentivize people to have continuous coverage. Should coverage be interrupted for more than 63 days, insurers would be able to charge a 30 percent penalty over the original premium for one year.

The CBO didn't release its cost estimate on the House bill until May 24, which projected that 23 million more people would be without health insurance over the next decade under the bill.

The Senate's version was supposedly crafted by a working group consisting of 13 Republican men -- and no women -- but one of the group's participants, Sen. Mike Lee, R-Utah, said even he had been left in the dark. Lee said the measure was "apparently being written by a small handful of staffers for members of the Republican leadership in the Senate."

Other Senate Republicans voiced frustration that the process had been too secretive and out of the public eye. Senate Republicans don't intend to hold any committee hearings on the bill, despite their commitment to so-called "regular order."

Nearly three-quarters of Americans said Senate Republicans should discuss their health care plans publicly, according to a CBS News poll released Tuesday. A quarter of the public, by contrast, said it should be developed in private. It also found 57 percent said Obamacare needs some changes, 28 percent said it should be repealed entirely and 12 percent said it should be kept in place.

CBS News' Nancy Cordes and Alan He contributed to this report.