Who will face President Trump in the 2020 election? So far, 24 Democrats have thrown their hat into the ring. However, once the first round of Democratic primary debates is over (June 26 and 27), expect a few candidates to drop out or fade away. (Four challengers--Steve Bullock, Mike Gravel, Wayne Messam and Seth Moulton--did not qualify for the first debates.) However, before that happens, let's take a look at what all 24 Democratic candidates have to say about an important campaign issue: taxes.

The Democratic party is moving to the left, and party voters want to know how each candidate will address income inequality as president. That means pushing progressive ideas on job creation, health care, higher education and other economic issues. Tax policy has to be part of the equation, too. Any broad new social programs will have to be paid for somehow, and that usually means tinkering with the tax code. Some candidates have big, bold tax plans, while others have ideas that are more modest and piecemeal. The voters will ultimately decide which path is best. It'll be months before the first Democratic primary ballot is cast, but it's not too early to start thinking about who will get your vote. When it comes to taxes, here's what all 24 Democratic primary challengers (in alphabetical order) are proposing. Start brushing up now, so you'll know who to vote for when the time comes.

Michael Bennet

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As part of his climate change plan, Sen. Michael Bennet is calling for tax incentives to encourage the use of zero-emission vehicles and transit programs. The credits could go to car manufacturers that sell zero-emission vehicles. He is also backing legislation that would create an investment tax credit for business and home use of energy storage technology. This tax break is modeled after the current investment credit for solar energy and would apply either to grid-connected energy storage systems or to residential battery systems.

Sen. Bennet is also behind a plan to overhaul the child tax credit. Currently, you claim the credit on your tax return and the credit amount is subtracted from your tax bill. Also, up to $1,400 of the credit is refundable (that is, you can get a tax refund for up to that amount if the credit is more than what you would otherwise owe). The revised credit under Sen. Bennet's plan would be paid to taxpayers on a monthly basis--$300 per-month ($3,600 per year) for children under six years of age and $250 per-month ($2,000 per year) for children under 17 years of age. So you wouldn't have to wait until April 15 each year to actually benefit from the credit. The credit would also be fully refundable.

The senator has also recently introduced or co-sponsored legislation to expand the earned income tax credit and to exempt AmeriCorps education awards from income tax.

Joe Biden

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Since throwing his hat in the ring in April, former Vice President Joe Biden hasn't presented a formal tax plan. He has, however, stated that he would repeal Trump administration tax cuts for corporations and the wealthy. He also wants to eliminate the step-up in basis for inherited capital assets, which means