I was there to witness, kuna muamko but the following is my observation:
There are many reasons we would be wrong to expect Chadema to win this election, its a wrong expectations, however. First, the electorate is not entirely stable.
Each generation of voters ( 1995-2015 one generation) has been a bit different from the last (1975- 1995 one generation).
It sometimes happens that over a series of elections, parties may be unable or unwilling to adapt their positions to broader socio-demographic or economic forces. Parties need to be aware of when society changes.
If leaders refuse to recognize that public opinion has changed, the party is unlikely to win in the next election. Groups that have felt that the party has served their causes in the past may decide to look elsewhere if they feel their needs are no longer being met.
Either way, the CHADEMA party system have been upended as a result of a party realignment, or shifting of party allegiances within the electorate