(CNN) In the last 24 hours, the following things have happened in the Democratic presidential race :

1) Former South Bend, Indiana, Mayor Pete Buttigieg ended his campaign and he's endorsing former Vice President Joe Biden in a Texas rally tonight.

2) Minnesota Sen. Amy Klobuchar decided to drop from the race and endorse Biden. She'll also be at that Biden Texas rally.

3) Former Senate Majority Leader Harry Reid (Nevada) announced his endorsement of Biden, citing the former vice president's ability to "assemble the largest, most diverse coalition possible to defeat Trump and lead our country following the trauma of Trump's presidency."

4) Illinois Sen. Tammy Duckworth , as well as a slew of other House members, former senators and former governors who represent states set to vote either on Tuesday or later this month, endorsed Biden.

This is what it looks like when the party establishment, deeply concerned about the prospect of Vermont Sen. Bernie Sanders as the Democratic nominee against President Donald Trump, starts putting the necessary pieces in place to try to keep the Vermont democratic socialist from winning.

How large are their concerns? Within 72 hours of Biden winning his first state in the nomination fight -- a larger-than-expected victory in South Carolina -- the entire field of pragmatic/moderate/establishment types have left the race, with the exception of free-spending billionaire Mike Bloomberg.

And you can bet that if Bloomberg doesn't wind up with more delegates than Biden after tomorrow, the former New York City mayor will come under huge pressure to put his ego aside and get behind Biden too.

(Now that doesn't mean that Trump's Twitter claims implying that Democrats are trying to " take it away " from Sanders are accurate. There is nothing nefarious about endorsements and drop-outs, this is just Politics 101).

Asked about the movement on Monday , Sanders told reporters, "Look, it is no secret ... that there is a massive effort trying to stop Bernie Sanders, that's not a secret to anybody in this room. ... The corporate establishment is coming together. The political establishment is coming together and they will do everything. They are really getting nervous that working people are standing up."

Still, it's not at all clear to me that the Democratic establishment can actually stop Sanders. The Vermont senator looks headed for victories in California and, to a lesser extent, Texas on Tuesday. And there's virtually no scenario I can imagine where Sanders doesn't end Super Tuesday with a clear delegate lead over Biden and everyone else.

The actual goal for the establishment may well to simply keep Sanders away from the 1,991 pledged delegates number that would formally make him the party's nominee.

Even if successful, of course, that effort would likely require superdelegates to decide the nomination -- in Biden's favor -- on a second ballot. Which, well, could be problematic.