Bernie Sanders has led an impressive campaign in the 2016 Democratic presidential race since he launched his bid in April 2015.

At the start of his run, the Vermont Senator was a long shot to win the White House. However, he has established himself as a strong contender, beating Democratic front-runner Hillary Clinton in the New Hampshire primary and nearly tying her for first place in the Iowa caucus.

In addition to being a longtime advocate for civil rights dating back to the 1960s, Sanders touts left-leaning politics on important issues like immigration, education and healthcare. As a result, his proposals for free college tuition and healthcare-for-all have distinguished him as a progressive hero and helped him win over young Democratic voters.

Here is where he stands on five key issues.

Immigration

Sanders supports a comprehensive approach to immigration that includes providing undocumented residents with citizenship and taking immediate action to waive some deportations.

"As president, I will fight for comprehensive immigration reform that provides a road map to citizenship for the 11 million aspiring Americans living in this country," said Sanders, the longest serving independent member of Congress in U.S. history, last November. He also said he would use his executive powers to help undocumented immigrants.

Sanders voted for the controversial "Gang of Eight" immigration reform bill in 2013, which would have provided undocumented immigrants with a pathway to citizenship. However, the bipartisan bill was stalled by Republicans in the House.

In addition, Sanders supports President Obama's executive orders to waive deportation for immigrants who were brought to the U.S. illegally as children, popularly known as DREAMers. He also promised to expand the president's executive actions. In turn, his plan would protect all undocumented immigrants who have been in the U.S. for the past 5 years from deportation. Furthermore, almost 9 million immigrants would be able to apply for deferred action.

Other proposals under Sanders' comprehensive approach to immigration reform include securing borders, respecting local communities, modernizing the visa system and rewriting bad trade agreements. These changes would help regulate the future flow of immigrants across the border.

Lastly, the senator promises to invest more funding into the overburdened federal immigration courts. Latin Post reported last year that the backlog in the court system increased by 68 percent from 2014 to 2015, bringing the number of pending cases to a whopping 445,706 in April 2015. Following the addition of nine new immigration judges this year, there are just 254 judges and less than 100 courts to handle all of these cases.

To address this issue, Sanders plans to work with Congress to provide additional funding and immigration judges to the Executive Office for Immigration Review. He would also restore discretion to judges and allow them to consider the unique circumstances of an individual's case.

Campaign Finance

A major part of Sanders' campaign is his proposal to limit the influence of corporate and special interest-groups in political elections. Sanders proposes a Constitutional amendment that would effectively reverse the Supreme Court's Citizens United ruling, banning corporations and nonprofits from donating unlimited amounts of money to campaigns.

The senator would also require all organizations to disclose information when spending $10,000 or more on an election-related campaigns.

Education

One of the most popular proposals in the Sanders campaign is the candidate's plan to provide free tuition at public colleges and universities, as well as free universal preschool for children up to the age of 4. Although this plan would drastically reduce student debt, it would cost taxpayers $75 billion each year.

To fund this proposal, he plans to raises taxes on the wealthy and some Wall Street transactions, which would generate about $300 billion in revenue.

Healthcare

Sanders has also called for a universal, government-provided healthcare system. According to him, President Obama's signature healthcare law, the Affordable Care Act, does not go far enough to protect Americans. Instead, his "Medicare for All" proposal would implement a single-payer system, in which the federal and state governments would provide healthcare to all Americans.

This would be paid for by a 6.2 percent income-based healthcare premium paid by employers and a 2.2 percent income-based premium paid by households. In addition, it would be funded by progressive income tax rates, taxing capital gains and dividends the same amount as income from work, limiting tax deductions for the rich, adjusting the estate tax, and savings from health tax expenditures.

Climate Change

A staunch climate change activist, the Vermont senator has proposed a bill that would charge companies for carbon emissions. He would then invest some of the money raised into renewable energy technology.

Sanders also plans to stop elected officials from selling out to fossil fuel lobbyists by banning the lobby from working in the White House. Although the fossil fuel industry has earned record breaking profits, companies also receive massive taxpayer subsidies through legislation passed by Congress, notes Sanders.

Watch Sanders lay out his immigration plan below.