“We’re going to need an innovative solution to reduce traffic here in Colorado, whether for our daily commute or for I-70 to the mountains. I don’t want us to risk being the very first to try an experimental technology, but if we can be 2nd or 3rd, we can benefit early on and help lead the way with new cost-effective technologies to reduce traffic,” Polis wrote.

https://www.coloradopolitics.com/news/insights-jared-polis-dreams-of-vegas-underground-while-building-country/article_6ff56548-29b9-11ea-9474-9b6a87e258e2.html