The Scott Brown’s victory in Massachusetts will most likely unleash a new torrent of bad news. Nervous Democrats are getting out (Arkansas Rep. Marion Berry is retiring) or not getting into races. And Republicans are licking their chops.

In Delaware, Joe Biden’s son has bugged out of the Senate race. Hotline observes:

The decision is a blow to Dems who hoped to mount a competitive race for the First State seat. [State Attorney General Beau] Biden’s decision makes Rep. Mike Castle (R) the overwhelming favorite to win the final 4 years of the senior Biden’s term, replacing Sen. Ted Kaufman (D) after the Nov. elections. Without the younger Biden in the race, Dems will likely turn to New Castle Co. exec. Chris Coons (D). Polls show Castle beating Coons by a wide margin.

And in Indiana, a new Rasmussen poll shows that it would be worth Mike Pence’s while to jump into the race against Evan Bayh:

Indiana Senator Evan Bayh is another Democratic incumbent who could find himself in a tough reelection battle this fall. A new Rasmussen Reports telephone survey of likely voters in the state finds that Bayh attracts support from just 44% or 45% of voters when matched against his top potential Republican challengers. . . At this time, [Pence]e attracts 47% of the vote while Bayh picks up 44%.

Even a much lesser known former Republican congressman, John Hostettler, is trailing the incumbent senator by only 3 points (44 percent to 41 percent). As Rasmussen notes: “Any incumbent who attracts less than 50% support at this point in a campaign is considered potentially vulnerable.”

This is the snowball effect of Brown’s victory, Obama’s decline in the polls, and the recognition that this will likely be a very bad year indeed for the Democrats. As the playing field of gettable seats expands for the Republicans, the problem will only worsen. The New York Times reports:

Just since Tuesday, half a dozen Republicans have expressed interest in challenging Democrats in House races in New York, Pennsylvania and potentially Massachusetts, party officials said. …

Tommy G. Thompson, the former Wisconsin governor, is considering challenging Senator Russ Feingold, a Democrat, aides said. Even in longer-shot states like New York, Republicans said they think the political climate gives them a chance to find a strong Senate candidate. … Stuart Rothenberg, a political analyst who follows Congressional races, said a report he will release Monday will count 58 Democratic House seats in play, up from 47 in December. The number of Republican seats in play has held at 14 in that period, he said. And Democrats expect more of their incumbents to retire, which could put additional seats at risk.

Political fortunes can change, the economy could pick up, and Obama might yet piece together some face-saving, modest set of health-care reforms. But without viable candidates to run in competitive races, Democrats will have put themselves at a disadvantage that is not easily repaired before the November elections. And one suspects that the retirements on the Democratic side are not at an end, nor have the recruiting efforts on the GOP side slowed. The end of the bad news for the Obama Democrats is not yet in sight.