There's no evidence of electoral interference -- and the Chinese care about their international reputation among developed nations unlike Russia -- I doubt they'd try it because of the costs if caught.
But there is plenty of evidence of them trying to seduce/bribe/compromise our politicians. Remember the honey-trapped Minister?
CSIS has considered China our most serious foreign threat since the late 1980s with the collapse of the Soviet Union, and they actually never shut up about it. No one seems to listen though:
2017: CSIS warns domestic company has technology militarily relevant to the American bloc ahead of the Chinese, the feds under the Liberals overrule national security decision under Harper to not sell the company to the Chinese state, saying the company should have "a second chance" at its security review (It's owned by the Chinese state!)
2016: CSIS: Russia and China out to steal Canadian secrets
2015: Ontario Cabinet Minister probably compromised by extraordinarily close Chinese ties, CSIS warns. Ontario Liberal Party dismisses all the concerns despite seemingly being well-founded.
2014: Same Minister was crucial to setting up a tie between a Chinese state-backed cultural outreach organization with the TDSB. Program for Chinese language and cultural education falls through when it appeared the Communist Party, not the Toronto schoolboard, was going to be setting the curriculum
2014: CSIS says China hacked NRC computer systems.
2013: CSIS publishes a lengthy report warning that among other things, China is actively compromising politicians and political organizations to facilitate its buy-up of Canadian natural resources in a pattern similar to what they've done in Australia.
2012: CSIS warns against oil buy-up deal that was approved anyway.
2011: CSIS: Canada a target-rich environment for Chinese spies
2007: CSIS: China is top espionage risk to Canada
It goes all the way back to the late 80s just like that.
Brock University Prof. Charles Burton, a former diplomat in Beijing, said he doesn't doubt Chinese espionage in Canada is significant. "It's well known from CSIS insiders that almost half of CSIS's resources are devoted to Chinese counter-intelligence exclusively and I would say we need more because clearly we're not on top of the situation," Burton told Sun News Network.