how much current is enough?

IMO you don't need to know that detailed current output.

Amp selection is controlled most importantly by the sensitivity of your speakers and your highest normal listening levels in YOUR room. Because your speakers are VERY insensitive AND low-impedance, you should look for a very-high-power amp that doubles its output power into 4 ohms. I'd say 250WPC into 8 ohms and 500WPC into 4 would be a good starting point.

If you love tubed amps, I recommend 2 stereo amps of at least around 75 + 75 watts. An amp like the (discontinued and hence 'affordable') conrad-johnson Premier Eleven is 70WPC into 8 or 4 ohms; with the 2 channels paralleled that turns into 140 watts into 4 or 2 ohms. In this case, using a stereo amp with channels paralleled is superior to using a mono amp of the same (combined) power rating, because the stereo amp will deliver that same combined power into half the impedance. If 140 'tubed' watts doesn't sound like enough to you, start with a higher-power stereo amp. For instance, an older c-j Premier Four will deliver 200 watts into 2 or 4 ohms from its combined 100-watt channels. Of course for stereo, you'll need 2.

I'm sure there are many more-current tubed amps that will do similar things and that you'll soon read about them from fellow 'Goners.
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Well, your Levinson is solidstate and those I mentioned are vacuumtubed. GENERALLY, when SS amps are 'monod', the channels are bridged so that the maximum power quadruples, not doubles. However, each channel drives only half the single impedance, so bridged SS amps are NOT high-current amps. The channels of tubed amps are paralled so they're generally able to increase current output enough to combine the output of the 2 channels. BTW, I understand that SS amp channels can be combined this way, but the only manufacturer I know of to recommend it is B&K.

For Mbacinello's VERY insensitive and low-impedance speakers, I am NOT recommending a bridged SS amp.
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"Another simmilar question...so if the mani-2's (which I dont as yet own...but am considering) are 81 db sensitive...that means that they will play 81 db with 1 watt, 84 with 2, 87 with 4 etc. That means that to get to the 110db, which their spec sheet says is their maximum volume level they would need 1024 watts of power."

Yes, your process is correct but I didn't check your arithmetic.

"..two things...is the sensitivity measured at 8ohms?"

No. 'Sensitivity', a term that became popular with solidstate amps, is the acoustic output measured 1 meter away from the speaker when driven with a signal that produces 2.83 volts into an 8-ohm test load (which happens to be 1 watt) and driven by a constant-current amp, which means solidstate, not tubed. 'Efficiency' is measured with 1 watt of input INTO THE APPROPRIATE LOAD, and that term is NOT used much anymore. So...sensitivity is measured with 2.83 volts into 8 ohms while efficiency is measured with 1 watt (into the load equal to the speaker's rated impedance). See below about Totem's rating.

"...such that a four ohm nominal speaker draws twice as much power from the amp?"

Yes, generally.

"...in which case those numbers should all be double and it would draw 2048 watts at 4 ohms to play 110 db?? and secondly, that's way more watts than the speakers can handle. Does that mean that they could never actually play as loud as there specs suggest??"

Well, sort of. As merge03 indicated, these things never work out exactly because, at least partially, they're based on subjective measuring techniques.

Merge03 also is absolutely correct in his statement that high listening levels are FAR easier and less expensive to achieve with more-sensitive speakers than with very-high-power amps. Also, it seems that achieving a sense or feeling of dynamic 'ease' is much-more difficult with low-sensitivity speakers and high-power amps than with higher-sensitivity speakers and less amplifier power.

BTW, the Totem Mani-2's sensitivity is eighty-FIVE, not 81dB, at least according to their website. That will reduce your power requirement to 300 - 400 watts for 110dB. And it appears to me they specify it inconsistently--"Sensitivity 85 dB/W/m.". If they're claiming to indicate efficiency, that indeed is stated in output at 1 meter with 1 watt of input. If they're claiming to indicate sensitivity, that's measured with an input of 2.83 volts into 8 ohms. There's a real difference.

Also, and this is STRICTLY personal, and I know NOTHING about Totem speakers, so PLEASE don't anyone overreact to my comment here: any audio-equipment manufacturer that says "Regardless of specifications, “Mani-2” channelizes primal energy and force into “being”" goes WAY down on my shopping list. That had to have been written by some marketing idiot who specializes in obfuscation, not elucidation.

And Blkadr is correct in writing that you need to try different amps with the speakers you love; I too should have emphasized that.

Personally, if high-quality sound at high listening levels were important to me, I'd start with a more-sensitive speaker.

Finding those reviews is the proverbial search for the needle in the haystack.

What's the exact term 'Sterophile' used for its sensitivity/efficiency rating?