I think the conversation, and the resulting political tie-in, is more about US franchise law and auto dealers dependence on said laws, than they are about an electric car, conservative ideology, or any particular politician.
Auto dealer groups comprise a powerful lobby with massive dollars to spend on politicians and long standing relationships with our governing bodies. These dealer groups are by and large threatened by Tesla's "direct to customer" model because it cuts them right out of the picture. Their greatest fear is once Tesla has cemented this as a viable and legal distribution method for their cars, what will stop other manufacturers from following suit and putting the franchise auto dealers out of business?
Thus, state and national auto dealer groups have been exerting whatever influence they can to maintain the status quo concerning franchise law, and this means standing in opposition to Tesla's business model. It really has nothing to do with the car, nor does it have anything to do with conservative thinking, or even that the car is electric. It is merely about the fact that lots of people who have been making lots of money for a very long time under current franchise law don't want to see that change. If it does you might begin to see manufacturers buying out their franchise dealers and running their own operations for sales and service in the US.
If all manufacturers go to this distribution model, or have it as an available choice, what does that mean for us?
1) Does that mean some of the prohibitive barriers to successfully producing and marketing a new car make have suddenly disappeared? I think that may be a yes, and that's possibly a good thing. More choice, more avenues for innovation and economic opportunity. On the downside, a lack of required infrastructure, like service facilities, dealerships where they have staff on hand to take care of the customers, etc. can make the ownership experience particularly daunting. I think Tesla has handled this right, however another company coming along after them might not. This is a major point of contention in the franchise law battle. Currently manufacturers are required to have a certain number of service facilities and sales floors.
2) Would widespread adoption of Tesla's business model by other manufacturers adversely affect prices? I think it *could* result in lower prices for cars and related services as you could cut out a middleman. However, imagine if every Ford dealer in your state was owned by the same company. That would reduce or even eliminate competition, and make it very easy to have institutionalized price fixing that would be very difficult to detect and prosecute. Less competition is bad for customers in general, and bad for companies as well as there is no drive to perform better, work harder, give better customer service than the other guy.
3) How will this affect jobs? The economy, etc.?
This really needs a lot of thought put in to it. Its not as simple as just saying, "Hey, its Tesla, its an awesome car, and an awesome idea, lets just let them do it." Its about all of the other manufacturers that are eying this exchange and getting ready to start pushing boundaries themselves. Where that will lead is really uncertain.