Posted Feb 4, 2012 11:39pm EST

Mitt Romney opened his new argument with Barack Obama in Las Vegas Saturday night: The economy, he said, is worse than you think.

The speech was nominally a victory speech, and the frontrunner pointedly ignored his rivals during his speech, alluding to them just once as "the other people running for president."

But there's a twist: Romney has built his campaign around the reality of a stagnant economy — that recent data suggests could be in the past.

Romney acknowledged the recent positive news but said that any economic improvement has occurred despite Obama, not because of his policies — a line of argument he will be forced to continue with as the general election begins.

"Mr. President, we welcome any good news on the jobs front, but it is thanks to the innovation of the American people in the private sector, not to you," he said.

The former Massachusetts governor and Bain Capital executive used his remarks to minimize Friday's jobs report showing unemployment dropping to 8.3 percent, calculating the true unemployment rate at over 15 percent, including those who've dropped out of the workforce or are unemployed.

That's the general election in a nutshell &mdash: An argument over the direction of the economy, in which the Republican may be reduced to selling pessimism.