However, the report says that the Conservatives were "more effective at distributing their message from the top", but "less so" at grassroots level.
Labour, on the other hand, has the "opposite challenge". Its supporters "drive conversations, yet the official line doesn't strategically trickle down", the report adds.
It describes the Lib Dems as "somewhere in between", with the party punching "above its weight" in follower numbers, but facing a challenge in "breaking into conversations that go beyond party supporters".
Its report says: "We believe that Twitter and other social media platforms, if used effectively, have the potential to impact the next general election in unprecedented ways that probably can now only be speculated - for the simple reason that many of these tools weren't around the last time the country took to the booths.
"It's a different ball game."
But, at his monthly press conference, Conservative leader David Cameron said he had no plans to start tweeting.
He said: "You need to use all methods of communication... The only problem I have is that politicians spend so much time talking, and giving speeches and giving interviews and on blogs and all the rest of it.
David Cameron: "You have to think about whether you'll be able to keep it up"
"Every time you add to the great panoply of communication you have to think about whether you can keep it up and whether you are going to fully think through everything say before you say it."
Meanwhile, 226 prospective parliamentary candidates are using Twitter, according to the report.
The Conservatives have most, with 78, followed by 63 for Labour and 42 Lib Dems.
The most-mentioned current MP on Twitter was Labour's Kerry McCarthy, who is also the party's new media campaigns spokeswoman.
The Scottish National Party had three tweeting MPs, while Plaid Cymru had two, and the SDLP and Respect had one each.
Tweetminster say its research was carried out over the year to 15 January.
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