First, your source is the "Washington Times", where Democrats are an endangered species.
Second, you quoted their reporters' interpretation of the meaning of the actual quote, which follows:
"This is the most secretive administration in recent history. This is an arrogant, out-of-touch administration that refuses to acknowledge that the Congress is a co-equal branch of government," said Jim Manley, spokesman for Senate Minority Leader Harry Reid of Nevada. "The vote last night demonstrates that a number of Democrats believe that Senator Biden and Senator Dodd have every right to ask for this information."
And the Senators do have every right to see the information they have been asking for for two months. It concerns Mr. Bolton's conduct as Undersecretary of State, and goes directly to the question of his ability to work at another diplomatic post. The Senate is charged with advise and consent functions in the Constitution precisely to act as a check on Executive power. It should not surprise anyone that Senators will complain when the Executive branch will not comply with requests pertinent to the Senate discharging its Constitutional function.
The White House's lack of compliance is about Mr. Bush and his phalanx; the debate, and the information requested, is still about Mr. Bolton.