Rubio: Biden is 'best thing we've got going'

In the hours leading up to the first debate between President Obama and Mitt Romney, Republicans are spending a lot of time talking about ... Joe Biden.

When the crowd at a Republican rally today in Denver hooted at the mention of Biden's name, Sen. Marco Rubio, R-Fla., replied: "No, don't boo -- he's the best thing we got going, guys."

Like presidential nominee Mitt Romney and other Republicans, Rubio mocked Biden for a mistaken comment yesterday that the middle class has been "buried" the last four years.

In criticizing the economic proposals of Romney and running mate Paul Ryan, Biden said in North Carolina: "How can they justify raising taxes on the middle class that has been buried in the last four years?"

Rubio hailed Biden for "a brief moment of clarity," in which he "told us what we already knew: The American middle class is hurting."

Obama campaign aides said Biden meant to refer to the George W. Bush presidency.

Campaign spokeswoman Lis Smith said Republicans are launching "another desperate and out-of-context attack" on Biden.

"As the vice president has been saying all year and again in his remarks today, the middle class was punished by the failed Bush policies that crashed our economy -- and a vote for Mitt Romney and Paul Ryan is a return to those failed policies," said Smith.

Don't be shocked if Romney mentions Biden during tonight's face-off with Obama in Denver.

Biden, meanwhile, gets to speak for himself when he debates Ryan next week.