From where does the money come?

"A survey conducted by Centre for Media Studies (CMS) pegs the amount to be spent on the 2009 Lok Sabha elections, which would determine the next government in the country, at about Rs 10,000 crore (USD 2 billion).
The estimated Rs 10,000 crore cost for the Lok Sabha elections includes about one-fourth or Rs 2,500 crore being spent through "unofficial money" or the cash to be paid to voters by the candidates, the CMS survey says.
According to the CMS study, the government spending would be about 20 per cent of the total expenses, including about Rs 1,300 crore by Election Commission and about Rs 700 crore to be spent by various central and state government agencies for purposes like photo identity cards, EVMs and polling booth.
Various political parties are expected to spend about Rs 1,650 crore from their party funds, which would include about Rs 1,000 crore from the two main parties -- Congress and BJP alone.
In addition to spending by parties, candidates of the national parties are estimated to put in Rs 4,350 crore, while those from the regional parties are expected to spend another Rs 1,000 crore."

From where these money comes? Do these political parties pay IT return on the money? If not, these money must be Black money or money landed by muscleman / Businessman with tainted desires?

So, if a government is made with 'big money with ill desires', how can Government stop ill things being happened? Where are we going to? Lets say if Pepsi/Coke or KFC/McDonalds has put their money, obviously they will sell it in higher prices. If liquor barons like Vijaya Mallaya or Cigarette making companies put their money- Govt. can not stop them selling the same, even if it is bad and should be banned. Why the inflation should not go up? Are the public of India fooled?