Working with NOP, market research firm Mori will be conducting an exit poll on 5 May and has to have the results ready for the BBC and ITV news teams that evening.
In an industry heavily reliant on information processing, any slight problems with IT could have a devastating effect on the company's reputation.
Ben Booth, Mori's chief information officer, said, "On the night we take a belt-and-braces approach. Everything has to be absolutely resilient.
"We always have business continuity in place and we do not want to lose time ever, but in this case we move to become more of a real-time business. Normally we can tolerate some interruptions to IT, but not on this night."
In the run-up to the election the IT department at Mori has avoided fundamental changes to its systems, including operating system upgrades and implementing new Windows service packs, Booth said.
Implementing any security patches has to be weighed up against the threat, he said.
"On the night of the election, I am going to be on call, at an event not far from our offices, so if necessary I can get there quickly.
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