Whichever party you belong to, there’s much to be gleaned from the note to clients Morgan Stanley’s Katy Huberty issued Tuesday about what she calls “iTV” (to distinguish it from the current Apple TV set-top box).

For starters, she’s got the results of a proprietary survey of 1,568 U.S. heads of household that she’s been sitting on since September. Key findings:

• 18% of Americans own a smart TV (i.e. with Internet capability) but only 13% know they do, suggesting that there’s a market for a smart TV that’s as easy to use as an iPhone or iPad.
• 11% of respondents said they would be “extremely interested” in buying an Apple-branded TV set, which translates into 13 million units in the U.S. alone.
• 36% said they would be “somewhat interested,” which could translate into another 43 million units.
• The 47% who were either “extremely” or “somewhat” interested is more than twice the 23% who said they were interested in buying an iPhone and the 21% who were interested in an iPad before either of those products were released.
• Respondents who owned at least one Apple device were nearly four times more interested in buying an iTV that those who did not.
• 46% of respondents were willing to pay over $1,000 for an iTV and 10% were willing to pay over $2,000. On average, respondents were willing to pony up $1,060, a 20% premium over the the average $884 they paid for their current TV set.
• Respondents aged 18 to 29 — the largest consumers of video over the Internet — were willing to pay the most for iTV: a 32% premium over their current set.
• Bottom line: iTV represents a $13 billion opportunity that could add $4.50 to Apple’s EPS.

Huberty’s note also reviews some of the TV-related patents that Apple has filed in recent years — everything from voice-controlled tuning to 3D screens.

Finally, she handicaps three different “go-to market” strategies — the stumbling block Steve Jobs identified when asked two years ago if Apple was ever going to fix television’s broken interface.

• Apple could become a full-blown virtual cable service provider.
• Apple could partner with existing pay-TV carriers and replace their set-top box with its own solution.
• Apple could bundle the TV set with its existing Apple TV digital media receiver.

Because Apple’s biggest media-device successes (iPod, iPhone, iPad) have been end-to-end solutions — including hardware, operating system and the packaging and distribution of content — Huberty favors the third option.

Because of the “headwinds” Huberty lists — including the 9-year life cycle of the average TV set and the 20% margins the TV market leaders (LG and Samsung) get on their sets — I’m growing increasing fond of the second.