House Democrats on Thursday joined Republicans in killing a proposal to allow counties to increase their MARTA tax rate, just days after Senate Dems fought to get it passed.

Both chambers then passed what one GOP lawmaker called a "stripped" bill, essentially changing it back to its original version and sending it to Gov. Nathan Deal's desk. House Bill 213 would eliminate the requirement that MARTA spend 50 percent of its revenues on capital projects and 50 percent on maintenance — giving the transit system more freedom in how it spends its money.

On Tuesday, Senate Democrats successfully amended the bill to allow Clayton, Fulton and DeKalb counties to ask voters to increase the MARTA sales tax from 1 percent to 1.5 percent. It was seen as a key piece of a deal that led Democrats to support HB 170, the massive transportation funding bill now on Gov. Nathan Deal's desk.

"A change of this magnitude to existing law should be reviewed in the interim and be reviewed within the context of House Bill 170 and within context of potential expansion of transit infrastructure and assure there's appropriate oversight," Speaker Pro Tem Jan Jones, R-Milton, said in proposing the amendment.

Both House Minority Leader Stacey Abrams, D-Atlanta, and Rep. Calvin Smyre, D-Columbus, the most senior member of the House, spoke in favor of the amendment.

“The language that will be voted upon in the amendment and the underlying bill will provide MARTA the relief they’ve sought for several years, allow us the opportunity to continue the expansion conversations we all agree we need to have,” Abrams said.

Senate Democrats had negotiated the deal for the sales tax as part of their negotiations over the big transportation bill, which they helped pass late Tuesday night. They thought they had a firm deal until Thursday morning, when it became clear things had begun to unravel.

The sales tax came into play as a way to win financial backing for transit improvements in metro Atlanta. MARTA is projected to receive about $400 million in the coming fiscal year from the existing 1 percent sales tax in MARTA’s jurisdictions — so passage of an additional half percent would have brought in an additional $200 million more a year in sales tax receipts.

That’s far more than MARTA stands to gain from a one-time allocation of $75 million worth of bonding that was included in the coming year’s budget, for which 128 transit providers across the state will have to compete.