Bitcoin has seen a sustained uptick in recent weeks and hit $8,000 in early trading Tuesday, prompting renewed interest in its comeback.

Bitcoin has jumped nearly 40% in the past week and has more than doubled in the past year, driving speculation of a comeback to 2017 levels. The cryptocurrency climbed above $6,000 last week for the first time since November and had traded at around $3,500 earlier this year.

Other cryptocurrencies — Ethereum, Ripple, Bitcoin Cash and Litecoin — have seen sharp gains over the past week.

Increased institutional interest may be driving the rally, with record cash inflows to Bitcoin Investment Trust (GBTC), a leading exchange allowing investors to hold Bitcoin indirectly.

Other explanations include positive sentiment around recent crypto conventions in New York and a potential safe haven from the U.S.-China trade war.

Another boost to the market is likely Samsung’s announcement in February that its flagship smartphone, Galaxy S10, is the first of a few phones updated for the cryptocurrency era, according to a company press release. Facebook, meanwhile, is building a crypto-based payment system.

Bitcoin remains far from its 2017 high of $20,000. It hit 60% market share during the recent rally and the last time it held that position was in December 2017 when Bitcoin was trading at its all-time high.

Digital currency experts have weighed in on reasons for the surge.

"I think that we've seen the bottom of the bear market [with Bitcoin]," Anthony Pompliano, founder and partner at Morgan Creek Digital Assets, said Tuesday on CNBC.

"There are literally dozens of reasons for Bitcoin to be surging right now but the important thing to remember is the main driver of this rally is increased adoption," Mati Greenspan, a senior market analyst at eToro, told Business Insider.

"Crypto fundamentals have been strong and building since early this year, when it was clear that we were oversold, and the continued parade of positive news and new retail and institutional offerings launching are firmly behind this bull market move," Jeremy Allaire, Circle co-founder and CEO, told