KEY POINTS
  • Longtime value investor Bill Miller remains bullish on bitcoin.
  • "Supply is growing 2% a year and demand is growing faster ... and that means it's going higher," Miller told CNBC on Tuesday.
  • "I don't think this is a bubble at all in bitcoin, I think this is now the beginning of a mainstreaming of it," Miller said.

Longtime value investor Bill Miller told CNBC on Tuesday he believes bitcoin is firmly entering into the mainstream, contending the cryptocurrency's rally in recent months is significantly different from its 2017 ascension and subsequent plunge.

In an interview on "The Exchange," the founder and chief investment officer of Miller Value Partners said he believes bitcoin still has room to run to the upside. The world's largest cryptocurrency by market value traded around $55,800 on Tuesday afternoon. It's already rallied around 90% year to date, according to Coindesk.