It came, they said, from the same wind that blew on Long Island in November, when a little-known Republican beat the favored Nassau County Executive Thomas Suozzi, who later conceded he'd miscalculated how tight the race was.
"You have a mixture of Democrats being demoralized and unhappy, and independents becoming more conservative," said Jay Jacobs, New York State Democratic chairman.
Bishop, once considered a safe bet but whom even Jacobs now lists as vulnerable, faces a well-funded opponent favored by national Republicans in businessman Randy Altschuler.
Wednesday, a new SurveyUSA poll for the liberal blog Firedoglake said Bishop is virtually even with Altschuler, leading him 47 percent to 45 percent. Bishop aides dispute the poll's accuracy and say their own polls show Bishop with more than 50 percent.
Gillibrand, though protected by the Democratic establishment, finds herself facing what appears to be a possibly potent primary challenge from Harold Ford Jr. And if she survives that, she could face GOP candidate Bruce Blakeman, a former presiding officer of the Nassau County Legislature.
Ford, a former Tennessee congressman, appears to be positioning himself as an independent to take advantage of the political currents. But Ford spokesman Davidson Goldin said "election results in other states have no bearing" on his "singular goal" to serve New Yorkers.
Hank Sheinkopf, a New York Democratic consultant, added, "Obama ran as a populist. He uncorked the bottle of populism." But, he said, "People don't believe in him anymore. They don't think the health finance reform is believable."
Republicans and Democrats differ sharply in their interpretations.
Republicans call it a sweeping shift, with voters rejecting President Barack Obama, the Democratic Congress and big-government policies like health reform. The GOP predict they will win big this fall.
But many Democrats downplay the impact of the upsets in Massachusetts and Nassau. They say an improving economy, breaking gridlock in Congress and a White House focus on jobs could allay voter anger over the next 10 months.
"What Massachusetts provides for us is an example of what can happen if Democrats don't take seriously the sour mood of the electorate," Jacobs said.
Altschuler, however, aims to tap voter anger and planned to meet last night with a "tea party" group, said his spokesman Rob Ryan.
Bishop said in an interview that he accepts he is in a very tough race, but the lesson he took away from Suozzi and Massachusetts is that he must work hard every day to win re-election.
"I am not thinking any different about the race," he said, because "I have never taken a thing for granted in my life."
An aide to Gillibrand offered a similar analysis: Democrats lost by not working hard.
"In every race she's been in, she's always been outspent but never been outworked," the aide said.
"Kirsten Gillibrand has had more than a dozen events last week. She's been to all 62 counties [in New York]. No one who's out there is working harder."