Countdown to the State of the Union

(NBCNC) - Tonight President Obama delivers his third State of the Union address, and he's taking aim at tax equality.

"We want an an economy that is based on everyone doing their fair share, everyone getting a fair shake and everyone playing by the same set of rules," says White House senior adviser David Plouffe.

The president wants to adopt the so-called "Buffett Rule" requiring that millionaires shouldn't pay lower tax rates than the middle class.

Republicans say it's sounding a lot like an election year stump speech.

"The President has been in total campaign mode since Labor Day and since the campaign apparently wrote the speech, I expect we'll hear a campaign speech," said House Speaker John Boehner.

The president is getting help from the most unlikely of sources: GOP presidential hopeful Mitt Romney is releasing his 2010 tax return and his 2011 estimate.

The documents show he earned more than $42 million over those two years, with an effective tax rate around 15 percent.

One of the invited guests tonight will be the now-famous secretary of Warren Buffett, who pays a higher tax rate than her billionaire boss.