The Tennessee branch of Americans For Prosperity (AFP) -- funded by conservative billionaires Charles and David Koch -- has been working with lawmakers opposed to mass transit projects in the state.

Think Progress reported that AFP has been not only credited with inspiring a bill recently passed in the state senate that undermines such projects through lane restrictions, but was thanked in a statement from a group opposing the Amp, a proposed $174 million rapid bus system in Nashville.

"It's pretty tough to fight that kind of money — AFP gets funds from the Koch brothers, and they're billionaires," Nashville Metropolitan Transit Authority (MTA) spokesperson Holly McCall was quoted as saying. "We continue to work our local campaign, and we're probably going to make some tweaks to the design — we're interested in compromise, because if we don't, our entire future transit plan is going to be dictated by people who live out of state."

The MTA said on its website that the Amp would help offset an influx of new residents -- nearly 1 million by 2035 -- by offering an alternative way for residents to commute, which would in turn cut down on drive times. The agency also argued that implementing the project would allow Nashville to remain competitive with other major cities benefitting from new public transportation investments.

"In Cleveland, a city that is otherwise experiencing economic challenges, the Healthline helped generate an estimated $4 to $5 billion worth of investment," the MTA stated. "And in Eugene, Oregon, $100 million worth of construction projects are underway near the Franklin EmX line."

However, last week the state Senate approved Senate Bill 2243, which includes an amendment banning agencies like the MTA and city governments from "constructing, maintaining or operating any bus rapid transit system using a separate lane, or other separate right-of-way, dedicated solely to the use of such bus rapid transit system on any state highway or state highway."

The Tennessean reported that a state House version of the bill, which lacks the amendment banning separate bus lanes, is scheduled to be debated on Thursday.

Andrew Ogles, the state director for AFP, told The Tennessean that his group has not contributed financially to local efforts opposing the Amp, but that SB 2243 did stem from a conversation he had with the bill's sponsor, state Sen. Jim Tracy (R)

Ogles also suggested that his group, which has been established for less than a year, saw an opportunity to use the state as a testing ground of sorts for future AFP efforts.

"With supermajorities in both houses, Tennessee is a great state to pass model legislation that can be leveraged in other states," Ogles was quoted as saying.