WASHINGTON - Jarred by new jobless alarms, Congress raced to approve legislation Thursday to keep unemployment checks flowing through the December holidays and into the new year for a million or more laid-off Americans whose benefits are running out.

The economic picture was only getting worse, if Wall Street was any indication. The Dow Jones industrials dropped more than 400 points for a second straight day, reaching the lowest level in more than five years, and the Standard & Poor’s 500 index fell below lows established six years ago.