They call you? that's insanity.
In Canada we don't have fixed election dates, so the advertising doesn't start until an election is called. Usually it lasts about six weeks.
There are also limits on how much they can spend, based on how many ridings the party is running in. Also, there is a limit to how much an individual, company, or union can donate to any political party, so that keeps things in hand a little as well.
Of course we also have way more than just two parties. Four parties are currently elected, one more is a national party with no seats, and there are dozens of fringe parties that are good for a laugh.
Personally, I love it all and can't get enough. But I am a political junkie. Elections are like my Super Bowl.