Representative Donna Edwards has mounted an unexpectedly competitive race for an open Senate seat in Maryland against party favorite Representative Chris Van Hollen, whose long list of backers include Senate Democratic leader Harry Reid of Nevada.

In Pennsylvania, the populist campaign of former Representative Joe Sestak has triggered a big spending campaign by the Democratic Senatorial Campaign Committee to help push Katie McGinty, a former state official, as its preferred standard-bearer to unseat Republican Senator Pat Toomey in November.

Later in the year, liberal firebrand Alan Grayson will take on fellow Florida Democratic Representative Patrick Murphy, who has the full backing of the Democratic Party, to be the nominee in the race for Marco Rubio’s Senate seat…

Gonzales said the new voters being fired up by Sanders’ campaign have a tendency to think less of candidates who are picked by Democratic Party officials. It’s something of a parallel with the Tea Party wing of the Republican Party, but instead of voters who think little of government, they “have a low view of the party establishment.”