https://coloradosun.com/2020/07/10/conservatives-for-yes-on-national-popular-vote/
Conservative group backing Colorado’s national popular vote measure fueled by out-of-state money, tied to Democrats
The campaign manager for Conservatives for Yes on National Popular, which is running ads in Colorado in support of the controversial law, declined to name a Republican in the state who has endorsed the measure
Here's an interesting run-down of the money going into the NPV repeal effort.