"2010 is a referendum on the very identity of our nation," Rubio said at the opening of the annual Conservative Political Action Conference. "Many of the old rules of political engagement will not apply."
The former Florida House Speaker is an upstart candidate challenging Florida Gov. Charlie Crist, who has been stigmatized in large part by a picture of Crist embracing the president at an event in support of Mr. Obama's stimulus package.
Rubio told a supportive CPAC crowd that Democrats are not trying to improve America as the country attempts to come out of recession, but rather change it -- and that conservative voters want candidates who stand in the way.
Candidates, he said, who will operate like the giant piles of compact, dirt-splattered snow that still stand tall along the streets of Washington, after a week of record-breaking snowfall.
That snow, Rubio said, was "the best thing to happen to the American economy in 12 months."
Washington was brought to a halt by the storm.
"The Congress couldn't meet to vote on bills," Rubio said to cheers. "The regulatory agency couldn't meet to set new regulations. The president couldn't find anywhere to set up a teleprompter to announce new taxes."
While voters want politicians to work together, Rubio said, "that comes with a very important caveat: it depends on what they're trying to do."
"America already has a Democrat party, it doesn't need two Democrat parties," he added.
One of Rubio's most high-profile supporters, Sen. Jim DeMint (R-S.C.), said obstructing the Democratic agenda will pave the way for a new Republican majority and help the GOP regain the public trust.
"I would rather have 30 Marco Rubios in the Senate than 60 Arlen Specters," he said.
Democratic Senatorial Campaign Committee Communications Director Eric Schultz released a statement following the speech knocking it as a rehash of "the same old, worn-out Republican talking points that led to economic collapse in the first place."
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