If you want to see what that might look like quantitatively, Ezra Klein has the goods. Based on analysis done by Boris Shor at the University of Chicago comparing the stated policy preferences as aggregated by Project Vote Smart for candidates, Klein looked at the 12 most competitive Senate races and their ideological split. What's potentially scary about this is what would happen if Republicans were to take over the Senate. There are some seriously extreme right-wingers there. But, here's the positive side. Look at the ideology over all among Democrats:
In Wisconsin, Connecticut and Massachusetts, our candidates Tammy Baldwin, Chris Murphy and Elizabeth Warren would all pull those seats to the left. Add in Martin Heinrich in New Mexico and Mazie Hirono in Hawaii, who are committed progressives on their way to the Senate, and we're looking at a much larger progressive bloc of Senate Democrats.
But first, we've got to get them there. So let's make that Senate upgrade happen. Please help do that by contributing to our candidates here.