GameStop Rally Rolls on

The explosive rally in GameStop (NYSE:GME) is showing no signs of slowing down as retail investors talking in chat rooms and hedge funds rushing to cover their short bets against the stock pushed it above $90 a share in early trading Monday.

Shares of the video game company soared another 40% in pre-market trading on Monday, following a 51% advance in the previous session in heavy trading. GameStop has rallied 245% in January alone, skyrocketing to $65 a share from just about $6 four months ago.

Those shares leaped $24.32, or 37.4%, soon after Monday’s open to $89.33.

Monday’s jump came despite a double-downgrade from Telsey Advisory Group. The Wall Street firm slashed its rating on GameStop to underperform from outperform, saying there’s a disconnect between fundamentals and valuation.

GameStop, a brick-and-mortar video game retailer, has been a popular short target on Wall Street. In fact, more than 138% of its float shares had been borrowed and sold short, the single most shorted name in the U.S. stock market, according to FactSet citing the latest filings.

Two weeks ago, news broke that activist investor and Chewy co-founder and former CEO Ryan Cohen is joining GameStop’s board. The stock jumped higher on the announcement on hopes Cohen would drive a change in strategy at the retailer.

The jump triggered a rush of short covering from hedge funds and traders who bet against the stock. When a shorted stock trades sharply higher, short sellers would have to buy back shares to cut their losses, which fuels the rally further.