Progressive Democrats had better hope Mary Landrieu loses -along with other moderate-to-conservative Democrats still in office (at any governmental level)- because their continued presence is an argument against their theory that the Democratic Party would be best served in future elections by moving further to the left.
I've no idea, but are there enough states to support a Senate majority with the coalition ideology you promote? I count Missouri, Indiana, North Dakota, Montana, New Hampshire, Louisiana, Colorado, Virginia (to a degree), and Florida as states where moderate Democrats survive and exist. Wiping them out and gaining Illinois, Maine (when Collins retires), and Wisconsin wouldn't net you the Senate. It'd actually benefit the GOP.
Taking out Virginia, which is turning more liberal and blue, -8 for the Democrats and -3 for the GOP nets the GOP 59 seats. Obviously this is rudimentary math, but moderate Democrats seem essential to the Senate majority.
The House also needs a fair number of moderate and conservative Democrats to form a Democratic majority, as well.
I am not the one demanding (either explicitly or implicitly) a purification of the party....
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