Vermont Senator Bernie Sanders announces presidential bid

Independent Vermont SenatorBernie Sanders said Wednesday he will run for president as a Democrat, promising to fight what he deems "obscene levels" of income disparity and a campaign finance system that is a "real disgrace."

In an interview with The Associated Press, Sanders confirmed his plans to formally join the race Thursday.

The self-described "democratic socialist" enters the race as a robust liberal alternative to Hillary Rodham Clinton, and he pledged to do more than simply raise progressive issues or nudge the former secretary of state to the left in a campaign in which she is heavily favoured.

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"People should not underestimate me," Sanders said. "I've run outside of the two-party system, defeating Democrats and Republicans, taking on big-money candidates and, you know, I think the message that has resonated in Vermont is a message that can resonate all over this country."

'Rigged economy'

As he has for months in prospective campaign stops in the early voting states, and throughout his political career, the former mayor of Burlington, Vt., on Wednesday assailed an economic system that he said has devolved over the past 40 years and eradicated the nation's middle class.

This is a rigged economy, which works for the rich and the powerful, and is not working for ordinary Americans.- BernieSanders

"What we have seen is that while the average person is working longer hours for lower wages, we have seen a huge increase in income and wealth inequality, which is now reaching obscene levels," Sanders told the AP.

"This is a rigged economy, which works for the rich and the powerful, and is not working for ordinary Americans. ... You know, this country just does not belong to a handful of billionaires."

The son of an immigrant from Poland who sold paint for a living in Brooklyn, Sanders has for decades championed working-class Americans. He lost several statewide races in the 1970s before he was elected mayor of Burlington in 1981, and went on to represent Vermont in the U.S. House for 16 years before his election to the Senate in 2006.

An independent in the Senate, he caucuses with Democrats in Washington and is likely to attract votes from the party's liberal wing.

But Sanders, 73, rejected the idea his appeal is limited to voters on the left, boldly predicting Wednesday that his message would appeal to both fellow independents and Republicans.

Sanders said he would release "very specific proposals" to raise taxes on wealthy Americans and corporations, as well as offer tuition-free education at all public colleges and universities. He touched on his past opposition to free-trade agreements, his support for heavier regulations of the Wall Street and the nation's banking industry, and his vote against the Keystone XL oil pipeline as a preview of his campaign.