Can I using nichrome wire to light a candle electronicaly?
I would look at purchasing some type of electronic ignition module (e.g. like those used for pilot lights in heating/hot water systems) but here are some thoughts regarding nichrome:

The 12V question - yes, if the supply can source enough current.  Nichrome will vary in ohms per metre for different gauges.
I have some nichrome wire here somewhere that is around 10ohms per metre (28AWG IIRC, see resistance table at bottom), which says it can be used up to around 1100 degrees centigrade.
I'm not sure of the exact temperature needed, but parrafin wax usually ignites around 199-249 C according to this page.
If we assume say 400 degress will be sufficient to start the ignition process (I'm guessing here, you will need to do some more research, or just try it out and see what works best) then using the table below we can calculate ~2A is needed for 28AWG (so your supply needs to be able to source at least 2A)
For ~10 ohms per metre and 12V, this would be 12V/2A = 6ohms, so 1m * (6/10) = 0.6m. So 60cm of 28AWG Nichrome wire across 12V should heat to around 400 C.     

Nichrome Temperature



Nichrome Resistance