DENVER, Colorado (AFP) — Barack Obama and Mitt Romney will not wait until the end of their first debate to proclaim themselves the winner or denounce the other’s claims — online campaign teams will already have done so.

While aides and other interested parties spun their message in Denver, Colorado ahead of Wednesday’s 90-minute showdown between the White House rivals, two competing websites will provide punchy live commentary.

Romney’s debates.mittromney.com and Obama’s www.barackobama.com/debate will vie for online supremacy when the debate starts.

Obama’s site was trailing a “Cheat sheet,” outlining what the Democratic candidate contends that Republican rival Romney will say to try and win favour, identifying jobs, taxes, and the US budget deficit as likely topics.

“While President Obama will lay out his specific plan to grow the economy and restore middle-class security, Mitt Romney will no doubt double down on his well-established strategy of attacking the president, distorting his own record, and avoiding any and all details of his plans for this country.”

Romney’s site, meanwhile, listed a set of “Debate Facts,” noting that the US had suffered a credit rating downgrade under Obama and said the national debt had risen by more than $5.4 trillion on the incumbent’s watch.

The site “will be the hub of our debate night efforts, fact-checking the Obama campaign as well as posting supportive material for our arguments,” Zac Moffatt, director of Romney’s digital campaign, told Mashable, a website.

On Twitter, the battle was already underway between Republican accounts, including the candidate’s official MittRomney and RomneyResponse, and the Obama side where BarackObama and TruthTeam2012 will lead the charge.

Obama’s top advisor David Axelrod, davidaxelrod, is likely to be active as is the president’s campaign spokesman Ben La Bolt, BenLaBolt on what are two of the most followed accounts among the Democrats.

An Obama-Biden email from Stephanie Cutter, the campaign’s deputy manager, received four hours before the president and Romney are due on stage, reminded followers about the debate section on the president’s website.

“In anticipation of what we’ll see tonight, I recorded a short video to give you some of the facts you need — so that you can set the record straight every time Mitt Romney lies or takes a cheap shot,” Cutter said.

“Check it out, and share it with others before tonight’s debate.”

A less partisan check on each of the candidates is likely to come from independent websites including politifact.com (PolitiFact on Twitter) and factcheck.org, both of which check the veracity of campaign statements.

Leading traditional news organisations, most notably The New York Times, have also upped their online game for the debate, with the “Gray Lady,” ready to publish elements on 76 subjects on the newspaper’s website when appropriate.

“We’re writing these fact-checks in advance so that we’re not scrambling,” said Mary Suh, a deputy politics editor at The New York Times, where 20 reporters have worked on the debate material.

“It’s all on an Excel spreadsheet — from Romney’s Bain history to Obama’s record on the deficit,” Suh added.

But Andrew Beaujon, a media reporter for the Poynter Institute, a non-profit journalism school, said social media had changed the game of making sure that politicians’ public statements are held to account.

“The interesting thing about this is, probably, the biggest fact checker is Twitter,” Beaujon said. “Not everybody will need a professional fact checker to look things up.”