Clinton's lead over Sanders shrinks as her edge over GOP vanishes

[Attorney in Texas]

21. If Biden runs, he and Sanders split the support of those voters who are uncomfortable with Clinton.

Because the progressive wing of the party is not big enough by itself to nominate Sanders without additional support from other voting blocks within the Democratic party, Sanders needs the united support from the progressive wing of the party (and he's got it) PLUS the united support of the not-Clinton segments of the party (this is where his campaign needs to grow).

Clinton is very popular among Democrats (for example, I'm a Sanders supporter and I like Clinton). After months of non-stop attacks from the 17 Republicans, from the NYT, from the WSJ, from FauxNews, from Mourning Joe on M$NBC, Clinton still has about a 75% approval rating and a 15% disapproval rating among Democrats so the not-Clinton segment of the party is not all that big. Still, if you add the not-Clinton segment of the party to the progressive wing of the party, you are approaching a consensus. Sanders is making good and steady progress toward building that consensus (and he's doing it the right way -- emphasizing policy differences and not attacking Clinton personally or with manufactured right-wing talking points).

If Biden enters the race, he splits the not-Clinton vote with Sanders so the math is not there for Sanders to enter the convention with 51% of the delegates. If you think Sanders enters finishes a three way race with Biden and Clinton were Sanders has 51% of the delegates and Clinton and Biden average about 25% of the delegates each, you are dreaming. With Clinton's campaign infrastructure and bank of endorsements and campaign funds and with Biden's status as the sitting VP, the centrist-establishment parts of the party will assure that the combined delegate total for Clinton plus Biden is more than 51% (regardless of whether Biden jumps in or not, Clinton's head start with party's centrists-establishment is so substantial that Biden probably cannot overtake Clinton among them so Biden is probably in a race with Sanders for second place and Biden's path to victory must involve either a brokered convention or taking the progressive support from Sanders, which I don't see happening). In a 3-way race, it is exceedingly unlikely that Sanders gets 51% of the delegates against Clinton and Biden.

You may ask what if Sanders gets 35% of the delegates and enters the convention with the highest delegate total because Clinton and Biden split the centrist-establishment delegates so evenly that Sanders squeaks out a slight plurality of delegates. Then we'd have a brokered convention. If you think for one moment that Sanders enters a brokered convention with Biden and Clinton, and Sanders comes out the winner, than you do not understand how brokered conventions work.

To get the nomination, Sanders needs to win 51% of the delegates. He can do it -- in fact he is on the exact path he would have to travel to accomplish this upset win over Clinton -- but he probably can't do it if Biden takes half of the not-Clinton vote.