For years, Republicans prospered by casting themselves as Washington's out-party, promising to clean house in the nation's capital. In 2004, President Bush and the GOP Congress will meet voters wearing a different face: the party of government.

This fall marks the first presidential election in nearly a quarter-century -- since Democrat Jimmy Carter's failed reelection bid in 1980 -- in which one party controls the executive branch and both chambers of Congress. Republicans have not faced this situation since Herbert Hoover followed Calvin Coolidge into the presidency in 1928.

The Republican grip on Washington, the result of a decade of electoral successes, paradoxically has left the party in a vulnerable spot. The absence of a divided government, which many voters seemed to embrace in the 1980s and 1990s, means GOP candidates must run, at least implicitly, as defenders of the status quo.

At least as Democrats see it, Republicans should be hard-pressed to avoid accountability for any result -- whether it is the course of events in Iraq or the size of the budget deficit -- with which the public is dissatisfied.

Even so, according to several outside analysts and strategists with both parties, Democrats have done little to advance this line of argument. Although polls show that the electorate nationally is intensely polarized, this fall's campaign has featured few expressly partisan appeals. In general, Republicans in their advertising have not urged voters to cast a down-the-ballot endorsement of GOP policies from the White House to Congress. Nor have Democrats made many attempts to urge voters to hold Republicans accountable as a party.

"The clear failure of the Republicans to govern well should be a much bigger issue than it is," said Simon Rosenberg, president of the New Democratic Network, an independent group that raises money and buys ads on behalf of Democrats. Their spots are among the few this year making an express partisan appeal, denouncing "four years of Republican control in Washington" and urging a Democratic vote to improve health care and jobs.

Some Democrats believe the relative dearth of such appeals is a missed opportunity, for two reasons. The first is what polls register as a general disquietude among voters about the country's direction under Bush. The other is specific ethics controversies involving prominent Republicans, especially House Majority Leader Tom DeLay of Texas.

By this reckoning, Democrats could cast Republicans as the party of entrenched power and self-dealing. This would be a turning of the tables, because this was precisely how Newt Gingrich (R-Ga.) cast Democrats during his successful bid to bring the GOP to power in the House in the 1994 election.

"It's hard to be the reform party when you are the party in need of reform," said Al From, chief executive of the centrist Democratic Leadership Council. "It gives Democrats a real opportunity to pin the tail on the elephant, and we probably need to do that more."

There are several reasons that candidates have not campaigned much on a party label, even in a year when partisan fervor seems to be running high. The most important, as various election analysts see it, is that the presidential race has revolved around the attributes and records of Bush and Democratic nominee John F. Kerry, rather than the message or records of their respective parties.

Meanwhile, the contest has been close enough that many candidates for other offices, worrying most of all about their own fate, do not have an incentive to urge people to vote a party line. This is in contrast to the way that many conservative Republicans ran expressly as part of the "Reagan Revolution," which ousted Carter and many entrenched Democratic senators in 1980.

In that year and others, said political scientist John J. Pitney Jr. of California's Claremont McKenna College, candidates could "surf to victory with a winning presidential ticket."

"But you can't surf without a wave, and for months 2004 has been an election of ripples," he said.

Many of the candidates in the toughest races have no desire to identify themselves with their national party. In North Carolina, former Clinton White House chief of staff Erskine B. Bowles (D) will probably need to run many points ahead of Kerry if he hopes to defeat Rep. Richard Burr (R) for an open Senate seat.

Although local factors sometimes vary in states or congressional districts, Republicans have typically run strongest nationally when they promoted a reform profile. That is what the GOP did in the 1980s, when it targeted congressional barons such as Thomas P. "Tip" O'Neill Jr. (Mass.) and Jim Wright (Tex.), both House speakers, as emblems of a smug and decadent Democratic majority.

The strategy reaped its greatest success in 1994, when Gingrich and his partisans swept to power with promises to modernize government, eliminate pork spending and overhaul rules governing how Congress does business. In 2000, Bush gained traction by promising to "change the tone" in Washington and by casting himself as a "reformer with results."

Last winter, DeLay announced that "if 1994 was the year we stopped thinking like a permanent minority," then "2004 is the year we start thinking like a permanent majority: unified, aggressive, rightfully confident of victory."

The GOP's reformist credentials lately have become a bit scuffed. DeLay has been reprimanded by the House ethics committee, including three times in the past month. A Texas grand jury recently indicted three associates of DeLay on charges of illegally collecting corporate contributions and funneling them to state legislative races. Beyond the majority leader, Republicans have drawn scrutiny in recent years for their "K Street Project," an effort to track interest-group lobbyist contributions and partisan affiliations to restrict access and jobs to supporters.

Democratic National Committee Chairman Terence R. McAuliffe called these controversies just one manifestation of a party that has too much power and is too focused on special interests, an argument he makes "in every speech I give."

"You talk about Republicans controlling all three branches of government," said McAuliffe, taking note also of the conservative majority on the Supreme Court. "There's a huge awareness that Republicans have moved the government to the right wing."

Even so, he acknowledged, the television ads through which most voters learn about the campaign are "more issue-specific," rather than making a broader party appeal.

Republican National Committee Chairman Ed Gillespie made a similar argument in reverse. GOP candidates generally are eager to position themselves as backers of Bush but do not necessarily play up a partisan message in ads because "that's not the way you reach people."

Although the number of voters who identify themselves by party has been steadily declining over decades, there are still circumstances when it pays to highlight party labels. Often, though, it is the other party's label.

In 1996, President Bill Clinton's reelection team warned what would happen if he was not in office to check the Republican Congress, an implicit acknowledgment that Democrats did not stand much chance of regaining a majority. GOP legislators, meanwhile, warned what Clinton would do if empowered with a Democratic Congress, an implicit acknowledgment that Republican presidential nominee Robert J. Dole was going to lose.

When asked in surveys, said Democratic pollster Mark Penn, a majority of voters say they prefer a divided government as the best way to ensure centrist policies. Still, this year has not presented the right circumstances to make a coordinated attack on Republican control a logical appeal.

"There really isn't a national message," he said. "People are trying to win with individual messages, and neither party wants to take its eye off the presidential ball."

President Bush, Senate Majority Leader Bill Frist (Tenn.), left, and House Speaker J. Dennis Hastert (Ill.) reflect the Republican dominance in Washington, a reversal of the party's role in the 1980s and '90s, when it attacked the Democratic establishment in the White House and on Capitol Hill.