Comedian and actress Roseanne Barr filed papers to run for the Green Party's presidential nomination. (Photo: GUS RUELAS / Reuters)

As Republicans battle for the GOP presidential nomination, the Green Party may have already found its standard bearer.

Roseanne Barr announced Thursday her campaign for president under the Green Party banner, denouncing the Democrats and Republicans who are bought and paid for by the 1 percent, according to The Associated Press.

The environmentally conscious third party welcomed Barr as a promising candidate. Barr still must go through the nominating process against another announced Green Party presidential candidate.

We look forward to a race based on Green ideas and values, and to showing the Democrats and Republicans how to run without the corrupting influence of fat corporate campaign checks and corporate-funded attack ads, the Green Party said in a statement.

Her candidacy may seem like a joke or publicity stunt, but the Green Party has a history of nominating celebrities who can attract votes and take campaigning seriously. Here are some of the more famous citizens who wanted to make politics a little greener.