Here’s a look at the odds for 10 of Bernie Sanders’ most ambitious proposals, according to Democratic aides, outside experts and Axios’ issue experts.

1) Medicare for All: Sanders is leading the charge on this idea. Unlike Democratic candidates who'd leave some role for private health insurance, Sanders is candid that he wants to wipe it out and replace it with a single-payer system.

This is one of the main ideas Sanders wants to get through Congress by using budget reconciliation, which only requires a majority vote in the Senate, not 60 votes.

But Medicare for All is divisive even among Democrats, the debates have shown. So it’s hard to see the path to 51 Senate votes — or even 50 and a Democratic vice president breaking the tie.

2) Eliminate medical debt. Sanders wants the federal government to pay the $81 billion in unpaid medical debt reported to credit agencies.

Though the price tag may be a tough sell for Democrats, debt can often be purchased for pennies on the dollar. Craig Antico of RIP Medical Debt, a charity that buys medical debt and forgives it, says his group might only need $800 million to buy $100 billion of debt.

The problem, he says, is that the total amount of unpaid medical debt in the U.S. far exceeds $81 billion — and a lot of it is not for sale.

It's not just the amount reported to credit agencies. His group estimates the total amount of unpaid medical debt is as high as $1.1 trillion — including hundreds of billions of dollars owed to hospitals and other health care providers.

3) Green New Deal: Not all Democrats support the Green New Deal. Some find it too aggressive, and Republicans are solidly against it. So even if Dems win the Senate, they'd still find it tough to count enough votes to pass the policy, Axios’ Amy Harder reports.

Sanders’ version would certainly be ambitious, aiming to shift to 100 percent renewable energy and reduce domestic greenhouse gas emissions by 71 percent by 2030. It would also be expensive — the campaign says it would cost $16.3 trillion.

4) College for All: Sanders says he’d make four-year colleges and universities free for all — at $48 billion per year — and also get rid of all $1.6 trillion in student loan debt, at a cost of $2.2 trillion over 10 years.

Even if he tried to pass this plan through budget reconciliation, it would likely run into trouble among Senate Democrats, since they’re likely to debate both the cost and whether tuition relief should be more targeted based on income.

5) Wealth tax: Like Elizabeth Warren’s plan, Sanders’ version of the tax could have a hard time getting enough Democrats support for Senate passage, much less Republican support.

The IRS would have a tough time determining the value of private wealth, and “if the taxpayer appeals, it can get drawn into a years-long court fight,” according to a Senate Democratic aide who works on tax issues.

6) Estate tax on millionaires and billionaires: Sanders would tax estates starting at 45% for estates of $3.5 million, ending with a top rate of 77% for estates over $1 billion.

The idea could be popular with many Democrats, but it has a big catch: By setting the starting threshold at $3.5 million — the level it was at in 2009 — it could be low enough to apply to family farms. That could make it hard for farm-state Democrats like Jon Tester of Montana to vote for it, according to the Senate Democratic aide.

7) Federal jobs guarantee: Sanders’ “Jobs for All” plan promises every American “a stable job that pays a living wage.” But the cost estimates could make Democrats think twice about it.

The centrist think tank Third Way notes one widely circulated model plan for guaranteed jobs would cost $560 billion a year to employ 10 million people.

Robert Reich, former Labor Secretary under Bill Clinton, tells Axios the cost would be “very hard to calculate” because of all the variables — but he believes net costs would come out to about $70 billion a year.

Even without the price tag, some Democrats are likely to reject the idea out of hand. "If you have a child 30 years of age [asking] where their allowance is, you got a problem," said Sen. Joe Manchin of West Virginia.

8) Decriminalize border crossings: This is one major area where Sanders could accomplish his goal without having to get approval from Congress. He could simply instruct his Justice Department not to prosecute border crossings, Axios’ Stef Kight reports.

His other big immigration goals — to put a moratorium on deportations, stop building Trump’s border wall and overturn the Muslim "ban" — could likely be accomplished through executive actions, too.

9) Expanded Social Security: Sanders wants to make Social Security benefits more generous. He would make the rich pay more, lifting the cap on the payroll tax that funds the program.

This one would need to be aired more widely, but a narrow Senate Democratic majority could be friendly to it (what Democrat wants to vote against Social Security?) Plus, the nonpartisan Committee for a Responsible Federal Budget says it could reduce budget deficits.

10) Link Israel aid to better treatment of Palestinians: Sanders has said he wants to condition U.S. aid to Israel on more respect for Palestinians’ right to live in “security and peace.” But he wouldn’t be able to make that change on his own — he’d have to convince Congress.

“Major shifts in aid will require support in Congress, and right now it's difficult to see a realistic pathway for implementing most of these ideas,” said Brian Katulis, a senior fellow at the Center for American Progress who specializes in the Middle East.

Alayna Treene contributed to this story.

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