WASHINGTON (AP) — Sen. Joe Lieberman’s primary defeat came at the hands of Democratic voters angry over the war in Iraq and demanding that lawmakers stand up to President George W. Bush rather than stand with him.It was not a polite message they sent their three-term senator, a former vice presidential running mate who fell to anti-war challenger Ned Lamont. It was an eviction notice, served on Tuesday by an electorate that has grown remarkably sour about the course their country is on.

That makes the result both an opportunity and a challenge for Democrats nationally as they head into an autumn campaign with control of the House and Senate at stake.

To triumph in November, Democrats will need the same intensity, including the support of bloggers and groups such as MoveOn.org, that powered Lamont to victory in Connecticut.

“I think there is huge dissatisfaction with the way the president is handling the war,” said Sen. Chuck Schumer of New York, the chairman of the party’s Senate campaign committee. “People are divided over whether we should have a strong, aggressive foreign policy, but there’s very little division even among those for a strong foreign policy that the president has really botched this in terms of having a plan, in terms of a direction, in terms of an endgame.”

The challenge for Democrats is that Republicans already are pointing to the anti-war activists who flocked to Lamont, and their penchant for edgy political tactics, as evidence that Democrats cannot be trusted with the nation’s security.

“We’ll soon find out just how significant this election is, but it’s a problem for Democrats long-term,” the Senate’s second-ranking Republican, Mitch McConnell of Kentucky, said after Lamont had won. “The McGovern wing of the Democrat party seems to have forgotten that we’ve been on offence for the last five years and that’s why we haven’t been attacked here at home.”

There is nothing new or surprising about such Republican rhetoric. Less than 100 days before the November midterm election, it has become obvious to Republicans that they can hardly afford to allow it to turn on a simple referendum on Bush and his policies. Stoking concerns, or even fears, about Democratic leadership served Republicans well in 2002 and 2004, the first two campaigns conducted in the shadow of the terror attacks of 9/11.

Their hope is it will work again this fall, particularly among swing voters who will settle key House races in Pennsylvania, Indiana, Ohio, Kentucky and even Connecticut.

However they handle their balancing act on the war, Schumer, Senate Democratic leader Harry Reid of Nevada and other party leaders who sought unsuccessfully to save Lieberman intend to swing behind Lamont as early as Wednesday. Lieberman expects it, and party unity demands it.

That does not mean the three-term incumbent intends to go quietly. In the same breath he conceded the primary, he vowed to run as an independent. He would join Lamont and Republican Alan Schlesinger on the fall ballot in a race that could again have repercussions beyond Connecticut. “Republicans are anxious to say the left wing is taking over, the antisecurity wing” of the Democratic Party, the three-term senator said recently, not exactly rebutting the claim as he repeated it.

It will be days before the polls can measure a three-way race with accuracy. A Quinnipiac survey in mid-July suggested Lieberman would head into the campaign in a strong position, finding 51 percent support for him, 27 percent for Lamont and 9 percent for the Republican.

With his primary victory, Lamont almost certainly will gain support, at least intially, in a three-way matchup. In defeat, Lieberman will lose it, and the next poll could produce far different results than the last.

In the final days of his primary campaign, Lieberman was fond of saying that in embracing Lamont’s candidacy, the voters were trying to send him a message and that they would in the end return to his side. He offered them a reason to do it, stressing his many differences with the president without changing his fundamental support for the war. It was more than that, though. In private polls, fewer than ten percent of Democrats surveyed said they thought the country was headed in the right direction, an extraordinary level of dissatisfaction. Lieberman, taunted as Bush’s best Democratic friend in Congress, bore the brunt of it.

Soon, Democrats hope, it will be Bush’s turn, or at least the Republicans who control the House and Senate.