In the corridors of Capitol Hill where the offices get grander, the perquisites get richer, and the patronage gets broader as seniority increases, rank has always had its privileges. But in the House of Representatives this fall, rank has its perils, too.

As campaigning begins in earnest for the Nov. 4 elections, some kingpins of the House's Democratic majority -- the second-and third-ranking members of the leadership and four senior committee chairmen -- face serious threats of involuntary retirement at the hands of well-financed Republican challengers who are attacking the leaders, in part, precisely because they are leaders.

Ways and Means Committee Chairman Al Ullman of Oregon and Public Works Chairman Harold T. (Bizz) Johnson of California are in the worst shape. Both generally are considered to be running behind and will have to fight like never before to save their seats.

Morris K. Udall of Arizona, chairman of the Interior Committee, is running no better than even in a district that seems to be growing more Republican every week. The Agriculture Committee chairman, Thomas Foley of Washington, appears to be slightly ahead now but remains a prime Republican target. The same is true of James Howard of New Jersey, whose chairmanship of the surface transportation subcommittee gives him hegemony over railroads and the interstate highway system.

The number two man in the House Democratic hierarchy, Majority Leader Jim Wright of Texas, and the number three man, Majority Whip John Brademas of Indiana, also face unusually tight races this fall, although both currently are favored by most political professionals to win reelection.

Two other veteran Democrats, Frank Thompson of New Jersey and John N. Murphy of New York, who gave up their chairmanships this spring after getting snarled in the Abscam scandal, may also lose their jobs this fall. Their political future may depend on a federal trial in Brooklyn next month, where they will be codefendants facing bribery charges.

The Abscam defendants have particular political problems, of course, and every House race has its idiosyncrasies. But there are also common threads linking the campaigns of all the endangered House leaders, and one of the most important problems they face is their prominence in Washington.

Most of the leaders facing tough reelection fights won't talk about their situation, fearing that candid admissions about their troubles would bring more contributions to the Republicans challenging them. The leaders also seem to fear that news of an uncertain political base at home might harm their chance to win higher leadership positions in the House.

But Udall, whose record as a presidential candidate, national convention keynote speaker and committee chairman have made him one of the best-known House members, conceded the other day that his celebrity is one of the reasons he is in political trouble.

"You just become a tempting target for the Republicans, for the rightwing money groups, for a lot of people who want to 'throw the bums out' and then say, 'We might as well start with the big names,'" Udall said. "And then the next year when they put out the brochure to get contributions, they can say, 'Look, we're effective, we got Mo Udall out.'"

A junior member of Congress, moreover, can plead his relative lack of power when voters complain about the way Washington runs the country. But as Udall noted, "If you say people should vote for you because you have seniority, you're a chairman, then they can decide that you must be responsible for all these horrible things the Republicans are talking about."

Another aspect of the phenomenon is that, as House members become more and more important in Congress, they get more and more tied to Washington and to national politics.

Sitting beneath a glistening crystal chanderlier that hangs from the arching marble ceiling of his boss's lavish Washington office, an aide to a senior House Democrat noted the other day that "when you sit in here, and the White House is on the phone, you sort of forget about the sewer grant for the 2nd District."

This seemed to happen in 1978 to Foley, the Agriculture Committee chairman, who found himself, after seven straight fairly easy campaigns, in a tough fight for survival. The voters, polls showed, felt that their big-name congressman had lost interest in the district, which includes Spokane and the northeastern corner of Washington.

Foley won that year with 48 percent of the vote, in a three-way contest. In the two years since, he has made himself much more visible at home and may have a slightly smoother road this year. His fate may hinge on the result of a four-way Republican primary election Tuesday.

Ullman, a 12-term veteran whose position as head of the House's tax-writing committee automatically makes him a Washington VIP, seems to face the same problem Foley had two years ago.

"He just has the image of a Washington congressman," says a Democratic campaign worker -- an image that was enhanced earlier this year when the local papers reported that Ullman no longer owns a home in his eastern Oregon district.

Ullman's challenger, Dennis Smith, the son of a former Republican governor, also likes to remind the voters that if they don't like the federal income tax their own congressman is the man to blame. Smith is geting money from some national groups that are opposed to Ullman because of various aspects of the tax code.

In Bizz Johnson's district, a sprawling piece of northeastern California, the incumbent's problems seem to be more traditional. After 22 years in Congress, the 72-year-old Public Works Committee chairman cannot match the vim and vigor of Republican Eugene Chappie, a state legislator who will have a ton of campaign money this fall.

And Johnson's position as head of the House's earth-moving and dam-building committee, while it does bring a lucrative flow of contributions, makes him a top target of some environmental organizations.

To the southwest, in Tucson, Udall's problems stem not so much from his committee chairmanship as from his national reputation as a liberal champion, a supporter of Edward M. Kennedy's presidential race and a leading spokesman for the Democratic Party. There are districts that might take pride in such things, but Udall's is becoming less like that all the time. As retirees and other immigrants to the Sun Belt take up residence in his district, Udall's home base is becoming Republican territory.

Udall is running hard to save his seat, but his challenger, Richard H. Huff, a real estate millionaire, is running even harder. Huff's commercials have been on the air for 11 months.

"I may go down," Udall acknowledges.

Wright and Brademas, of the Democratic leadership, are in less jeopardy than Udall, but neither can be considered as safe as top House leaders usually are. Both have been required, because of their positions in Congress, to vote the Democratic Party line more often than their districts would like; and thus are open to the suggestion that they are too liberal for the people they represent.

Both, moreover, have to live with a suggestion of as yet unproven scandal. Brademas' close friendship with Korean agent Tongsun Park in the 1970s made his name prominent in the "Koreagate" investigation two years ago. Wright is pestered by news stories about questionable oil deals.

Howard, the commander-in-chief of the nation's federal highway network, would be in line to take the chair of the full Public Works Committee if Johnson were defeated this year -- but first Howard will have to keep his own seat. His district, which includes a prime chunk of the New Jersey shore, is attracting conservative migrants much as Udall's has.

Howard is fortunate that Republicans are focusing on some other New Jersey races, including the one in Thompson's district around Trenton. But if challenger Marie Muhler can get money and assistance to offset the large contributions Howard receives from highway-building interests, she may add the subcommittee chairman's name to what may be a long list of fallen Democratic leaders.