Late last month, Apple (NASDAQ:AAPL) CEO Tim Cook stated that he had high hopes for "an iPad Christmas." He has good reason for optimism. This month, Apple has released not one, but two critically acclaimed iPads: the iPad Air, and the iPad Mini with Retina Display. Apple also dropped the price of the original iPad Mini from $329 to $299.

Apple's new iPad Air received great reviews, and early sales seem strong. Photo: Apple.

Despite all of these great things, Apple analysts are surprisingly glum in their prognostications about the iPad. Most analysts expect minimal growth for the iPad this fall, despite the double product refresh. However, the strong response to Apple's new product lineup -- especially the full-size iPad Air -- could be setting the stage for a blowout holiday quarter.

Meek expectations
In the December quarter last year, Apple sold a record 22.9 million iPads, representing nearly 50% year-over-year growth. This year, most analysts are predicting single-digit unit growth, with a few even looking for a year-over-year decline.

For example, Steve Milunovich of UBS is one of the more bullish analysts, and expects Apple to sell 25 million iPads this quarter (which he still calls a disappointment). At the other end of the spectrum, Kulbinder Garcha of Credit Suisse expects sales to drop to 21.8 million units. Ming-Chi Kuo of KGI Securities and Michael Walkley of Canaccord Genuity are in the middle, with shipment estimates of 23.1 million and 24.7 million, respectively.

It appears that one of the big reasons for analysts' low expectations is that the iPad Mini with Retina Display is supply constrained. Many analysts have stated that production problems could keep supply to as little as 2 million units for the whole quarter. Others think that Apple might be able to produce (and sell) as many as 4 million.

Overblown concerns
I'm skeptical of the most dire supply projections for the iPad Mini with Retina Display. Apple's decision to do a "soft launch" for the Mini does suggest that the supply constraints are real. On the other hand, several days after launch, the lead time for online orders in the U.S. was just one to three business days for the 16 GB and 32 GB Wi-Fi models.

The iPad Mini with Retina Display is in short supply -- but just how short? Photo: Apple.

Consider that Apple sold 3 million iPads in just three days after the fourth-generation iPad and the iPad Mini were released last year, most of which were iPad Minis. If Apple really had just 2 million units of the iPad Mini with Retina Display for this whole quarter, wait times should be expanding much more quickly.

Additionally, it is important to remember that supply constraints are nothing new for Apple. Last year, Apple managed to sell 22.9 million iPads despite significant supply constraints for the iPad Mini. Many of the 19.5 million iPads Apple sold in the March quarter went to meet pent-up demand.

iPad Air and iPad Mini will drive sales
In any case, Apple can put together a very strong "iPad Christmas," even if sales of the iPad Mini with Retina Display are severely limited by supply constraints. First, the iPad Air seems to be selling very well in its first two weeks on the market. The iPad Air already accounts for nearly 2% of all active iPads, according to Fiksu. That's a much faster adoption rate than what was seen for last year's iPad launches.

If that statistic is accurate, it suggests that around 3 million iPad Airs are already in use, and the holiday shopping season hasn't even arrived. (That also doesn't count iPads that have been shipped to retailers, or iPads that have been purchased but not used yet.) Another positive data point for iPad Air demand is that shipping times on the U.S. Apple Store have increased to five business days or more, up from 24 hours at launch.

The original iPad Mini is also likely to be a big seller this quarter. In recent years, cheaper tablets have been popular with gift-givers. The iPad Mini may have lower specifications than Apple's two new iPads, but for many people -- like my Foolish colleague Tim Beyers -- it's good enough. At its new $299 price point, the original iPad Mini could be a bigger seller this year than it was last fall (when supply constraints held back sales).

Don't count out the original iPad Mini. Photo: Apple.

The ready availability of the original iPad Mini and its lower price make it a good promotional vehicle this year. For example, Wal-Mart is offering a $100 gift card with the purchase of an iPad Mini for Black Friday, in a bid to reverse weak store traffic. That brings the effective price to just $199! This will undoubtedly be a huge sales driver.

Foolish bottom line
Apple analysts, who are expecting single-digit growth (or worse) for the iPad this quarter, are likely to get a big surprise when earnings come out in January. The strong reception of the iPad Air should boost sales of full-size iPads, while the lower price, and better availability of the iPad Mini, should make it a top holiday gift this fall.

That should be enough to overcome the supply constraints holding back sales of the iPad Mini with Retina Display. As a result, I would be surprised to see anything less than double-digit growth from the iPad product line this quarter. In fact, I think iPad sales could easily hit 30 million -- which would make Apple investors very happy campers.