Brooklyn-born Bernie Sanders marched on Washington in 1963, moved to Vermont the next year and ultimately ran six statewide races there (lost four, won two). The nation’s only socialist (he currently says democratic socialist) member of Congress tells high school students to argue with their parents and teachers and is an ardent anti-war activist who fought for military veterans. He has been a popular mayor, a Senate committee chairman, an early social media and filibuster phenomenon and he once recorded a folk album in the style of William Shatner.

Here is where he stands on 10 key issues.

Campaign finance: Limit corporate and interest-group spending in campaigns.

Sanders proposes a Constitutional amendment that would effectively reverse the Supreme Court’s Citizen United ruling and ban corporations and nonprofits from unlimited campaign expenditures. The independent senator would also require disclosure of any organizations spending $10,000 or more on an election-related campaign. Sanders is the only 2016 candidate who has rejected assistance from a super PAC, the financial organizations made legal by Citizens United.

Climate change: Charge companies for carbon emissions.

Considered to be a “climate change hawk,” Sanders argues that shifting global temperatures are a significant threat and caused by human activity. He has sponsored a bill which would charge companies for their carbon emissions and use some of the money raised to boost renewable energy technology.

Watch the PBS NewsHour Democratic Primary Debate, 9 p.m. EST Feb. 11, on your local PBS station, and in our live stream, which will begin at 8:30 p.m. Watch a live stream with closed captions here.

Education: Free, universal preschool. Free tuition at public colleges and universities.

The Vermont senator would make preschool free for all four-year-olds, funding the plan by increasing taxes on the wealthy and some Wall Street transactions. He would use similar tax changes to fund his key higher education proposal: to make tuition free at public colleges and universities. His campaign estimates that will cost $70 billion a year. In the past, Sanders has proposed funding state governments so they could cut tuition at state colleges by 55 percent.

READ MORE: What does Hillary Clinton believe?

Federal Reserve and banks: Break up big banks. Open up the Fed.

Sanders would divide large banks into smaller entities and charge a new fee for high-risk investment practices, including credit default swaps. In addition, he believes the Federal Reserve is an opaque organization which gives too much support to large corporations. His pushed for a 2011 audit of the Fed and he would use the Fed to force banks into loaning more money to small businesses. Finally, he would ban financial industry executives from serving on the 12 regional boards of directors.

Guns: Ban assault weapons. Repeal law protecting some gun manufacturers. No federal handgun waiting period.

In early 2016, Sanders changed his position on a gun law that protects some gun manufacturers and sellers from civil lawsuits. Sanders supported the measure in 2005 while in the House of Representatives. He now is co-sponsoring a bill to repeal that law. In the House of Representatives, Sanders voted against the pro-gun-control Brady Bill, writing that he believes states, not the federal government, can handle waiting periods for handguns. Soon after, he voted yes for the 1994 Violent Crime Control and Law Enforcement Act that included an assault weapons ban. He voted for the Manchin-Toomey legislation expanding federal background checks.

Healthcare: Launch universal, government-provided health care.

Sanders voted for the Affordable Care Act, but believes that the new healthcare law did not go far enough. Instead, he espouses “Medicare for all”, a single-payer system in which the federal and state governments would provide healthcare to all Americans. Sanders’ team estimates this will cost $13.8 trillion over ten years. He would fund the plan with a health surcharge or “premium” to be paid for by employers and individuals and by a new progressive income tax, raising rates for those making over $250,000. His top individual income tax rate would be 52 percent.

Immigration: Offer path to citizenship. Waive some deportations now.

Sanders generally agrees with President Obama that most of the undocumented immigrants in the country now should be given a path to citizenship. He voted for the senate immigration bill in 2013, which would have increased border security and issued a provisional immigrant status to millions of undocumented residents once some significant security metrics had been met. In addition, Sanders has supported President Obama’s use of executive orders to waive deportation for some groups of immigrants, including those who were brought to the United States as children.

Taxes: Raise income tax rates for those making over $250,000. Tax capital gains the same as dividends from work.

Sanders has long advocated a more progressive tax system. To pay for his $13.8 trillion “Medicare for all” plan, Sanders would increase income tax rates for those earning over $250,000, boosting their rate to 37 percent. Those at the top end of the income scale — earning more than $10 million a year — would pay 52 percent in income taxes. Sanders would also increase other fees or taxes, including Social Security taxes for higher incomes. In addition, he would tax capital gains at the same percentage as income a taxpayer makes from work.

In 2015 Sanders asked President Obama to use executive action to close six tax deductions benefitting corporations and hedge funds.

Iraq, Islamic State and Afghanistan: Opposed the Iraq war. Calls for troop withdrawal as soon as possible.

A longtime anti-war activist, Sanders voted against the Iraq war resolution in 2002. He has regularly called for the U.S. to withdraw troops from Afghanistan and Iraq as soon as possible. Regarding the Islamic State, Sanders has said the U.S. should not lead the fight. In general, he believes the U.S. should focus less on international conflict and more on the domestic needs of the middle class.

Iran and Israel: Supports current deal with Iran. Critical of Israeli Prime Minister Benjamin Netanyahu’s speech to Congress.

Sanders backs President Obama’s negotiations with Iran and sharply criticized Republican senators who signed a letter warning Iran against a potential deal. In a statement, the Jewish senator pushed back against the idea of tougher sanctions and was critical of Netanyahu’s speech to Congress. Sanders was the first senator to announce he would not attend the speech.

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