Democratic presidential candidate Bernie Sanders challenged frontrunner Hillary Clinton on her paid speeches to Wall Street on the eve of a crucial voting day, with five more states headed to the polls on March 15. (Reuters)

During Monday night's MSNBC town hall -- the 200th so far this month, by our count -- Bernie Sanders made a comment that raised some eyebrows among supporters of Hillary Clinton.

Asked by an Ohio voter why he chose to run as a Democrat, despite having served for years as an independent, Sanders explained his thinking. "We did have to make that decision: Do you run as an independent? Do you run within the Democratic Party?," he said. "We concluded -- and I think it was absolutely the right decision -- that A) in terms of media coverage, you had to run within the Democratic Party." (B, if you're curious, was that you needed to be "a billionaire" to run as an independent.)

The Fix's Philip Bump explains why Bernie Sanders essentially had to run as a Democrat, not an independent. (Peter Stevenson/The Washington Post)

It's understandable that dyed-in-the-wool Democrats would find this annoying. Imagine, a politician so crass as to leverage the resources available to him in order to win an election! But from that standpoint, it's worse than they think.

Last month, we noted that the emergence of the Internet allowed candidates like Sanders to be viable in ways that they couldn't have been two decades ago. Sanders's massive small-donor fundraising capability is solely a function of technology: one-click contributions and text message replies. The emergence of the now-infamous Berniebro -- Sanders's sometimes-painfully energetic base of support on the Internet -- is a function of the ability of the web to create pockets of individuals with a shared focus and interest. Technologist Clay Shirky had a series of tweets that made the point neatly.

But that last point from Shirky isn't entirely correct. The party has one essential resource: A well-defined path to the presidency, which has been exploited more clearly on the Republican side. Donald Trump hopped the Maginot Line that the Republican establishment set up to protect its well-trampled path to the White House, and now Trump is marching along, unfettered. That's what Sanders wanted, too: The attention and processes that make a candidate viable in the eyes of more than just a few thousand people on Twitter.

What's important to note is that Sanders isn't just hijacking the party's processes -- he's hijacking the results.

If you look at the exit and entrance polling reported by CNN, you'll notice that Sanders consistently does far better with independents that vote in the Democratic primaries and caucuses. It's fairly simple to figure out how much of Sanders's support in each contest comes from independent voters. In many cases, it's nearly half.

To put a fine point on it: In eight of the 15 contests for which we have data, 40 percent or more of Sanders's support came from independent voters.

In at least three states -- New Hampshire, Oklahoma and Michigan -- those independent votes likely handed Sanders the win.

Exit and entrance polls are estimates, with their own margins of error, so it's important to note that the figures at play are not hard and fast. Which holds true for the next point as well.

If you look solely at the Democratic vote in the 15 contests for which we have exit polling and apply the margins to the delegate counts in those states, it's likely that the 214-delegate margin currently enjoyed by Clinton would be at least 150 delegates larger. If Sanders wouldn't have hit the delegate thresholds in Alabama and Mississippi, as seems likely, the spread would be larger still.

Sanders ran as a Democrat because he recognized that blazing his own trail through the political wilderness didn't make sense. The party -- a party with which he has caucused for years -- had already done that hard work. But Sanders is competitive because he has organized an Internet-based army and because he is getting huge support in primary voting from independents.

If what party elders take away from Sanders's MSNBC comments is that he doesn't really care about or need the party -- that last part is mostly true.

Further reading:

Time magazine labels Bernie Sanders a ‘de facto millionaire.’ Not really.

7 Trump- and Sanders-infused primaries that are worth watching today

Why Hillary Clinton’s delegate lead over Bernie Sanders is bigger than it looks

Larry David returns to SNL, rips into Bernie Sanders supporters