Groupon's road show for its public offering sure paid dividends.  What began as a tough sell for founder and CEO Andrew Mason and other company executives -they were peppered with questions about company management, accounting and business model, ended on a tremendously positive note. First stop was at New York's St. Regis Hotel in mid-October before a packed room of 300 investors.  CEO Mason told the audience that Groupon operated in a market "measured not in billions but trillions of dollars" and added that "we’re just getting started.” His pitch worked because by Thursday morning, 11/3, demand had peaked for shares of Groupon.  By day's end, company executives and Wall Street underwriters were able to price the next day's IPO at $20, above the expected range of $16 to $18.  At this price, the company is valued at $12.65 billion. Lack of Supply. Demand, in part, was driven by a lack of supply, because the current owners are holding on to their stakes.  Initially, only 35 million shares - or 5% - of its total outstanding is being offered.  It’s an exceptionally small allocation, though it’s not a novel template. Several other Internet companies that went public earlier this year also favored small offerings to help support their stock prices.  LinkedIn, for example, which went public in May, initially sold under 10% of its total stock;  on Thursday it announced plans to sell additional shares. By comparison, U.S. technology companies typically have offered about 1/3 of the outstanding share pool, according to Thomson Reuters. Next Test for Groupon. That comes Friday, when company shares start trading on Nasdaq.  If shares do well - i.e., experience a significant pop - it could trigger a strong wave of Internet-related IPO’s from Zynga, Facebook and others.  On the flip side, a weak showing could dampen enthusiasm for the broad sector.  But, again, the small size of the offering will favor a big bump in share price.  And so, we have the likely template for future offerings in the sector - for better or worse.   [DealBook, 11/3/11, 7:16 pm]