Speculators clamored for call options on Crocs, Inc. (NASDAQ:CROX - 17.94) during the course of Tuesday's trading, with 4,302 of these bullishly oriented contracts crossing the tape -- representing more than three times the stock's average daily call volume. Meanwhile, fewer than 500 puts changed hands on CROX, accounting for only 73% of the equity's typical one-day activity.

Most of the action was centered on the September 19 call, where 3,038 contracts were traded. The majority of these calls traded near the ask, at a volume-weighted average price (VWAP) of $0.26. Implied volatility on this front-month strike rose 5.7 percentage points by the close to 41.4%, and open interest on the September 19 call jumped overnight by 2,612 contracts. Now, this out-of-the-money strike is home to peak front-month call open interest of 3,693 contracts.

In other words, it's safe to assume that new bullish bets were initiated here on Tuesday. Based on the VWAP of $0.26, breakeven on these purchased 19-strike calls stands at $19.26 -- some 7.4% above CROX's close yesterday at $17.94. Year-to-date, the shares have already advanced 21.5%.

However, there's a significant technical hurdle standing in between these call buyers and their potential profits. CROX is trading south of its 50-week moving average, which has served as resistance since late 2011. In the intervening months, the stock has managed just one weekly close above this looming trendline.