Television may have reshaped America's marketplace, revolutionized its politics and even influenced the course of wars. But change the United States Senate? Forget it.

A year ago, as the Senate tiptoed apprehensively into the television era, there were dire warnings from some influential senators that the lure of the camera would lead to grandstanding, gridlock and erosion of everything that made the Senate unique in the American political system.

There were also hopes, expressed by others, that television would help the Senate shape up its act and behave in a little more orderly, efficient manner.

But, as the Senate yesterday observed the first anniversary of its television debut, it was still its creaky, cranky old self -- a little nattier in dress, perhaps, but as windy, undisciplined and obstinate as ever.

It remains, as the Founding Fathers envisioned, "the saucer in which the passions of politics are cooled." Senate Minority Leader Robert J. Dole (R-Kan.) put it in more contemporary terms. Television gets "four stars" for bringing the Senate to the people but "two stars" for bringing efficiency to the Senate, he said.

"Let's just say we are continuing to improve," he added. "As long as the viewers can dial in their democracy, we will have to improve."

As it wound up its work under Republican leadership last year, the Senate amassed a solid record of achievement, including overhaul of tax and immigration laws, but had to go into overtime, well past its scheduled adjournment date, to do it all. This year, under Democratic control, it got off to a fast start, only to stumble over filibusters and other delaying tactics in dealing with some of its most contentious issues, such as arms control.

As if to underscore its refusal to bow too low to the robot-cameras that hover over the chamber from the galleries, the Senate was largely absent yesterday as Majority Leader Robert C. Byrd (D-W.Va.) and Dole saluted the anniversary with flowery speeches.

Then viewers were treated to a familiar message scrawled across their screens: "The Senate is in recess."

While television has had little impact on the Senate, it is less clear how much effect, if any, the Senate is having on American television viewing habits.

According to C-SPAN, the cable network that provides start-to-finish coverage of Senate and House proceedings, the Senate broadcasts are now available to more than 9.5 million households, compared with 27 million households that are equipped to tune into House sessions.

Moreover, the major television networks are regularly using snipets of Senate debate in their coverage of news events, ending the House's dominance of the airwaves and shifting the public's perception of the Senate from committee hearings to chamber itself.

And some senators, such as Dole, who are pursuing presidential nominations, are using the floor as a platform for displaying their skills and messages, mindful of the cameras that are always upon them.

But there is a strong suspicion among many senators that "As the World Turns," "The Young and the Restless" and other daytime soap operas need not worry unduly about their ratings.

In a speech entitled "TV in the Senate Is Putting the Country to Sleep," Sen. William Proxmire (D-Wis.), an unreconstructed opponent of televising the Senate, said one reason television has had so little effect on the Senate is that senators realize that "nobody, and I mean nobody, is watching."

Based on what he's heard from constituents and others, Proxmire said, "we might as well turn off the lights, sell the cameras, close down the television of Senate proceedings and send the proceeds to the Treasury to help reduce the deficit."

Byrd, principal sponsor of the legislation to televise the Senate, took a more optimistic view. While stopping well short of claiming that the Senate was everyone's favorite television show, he contended that its broadcasts had done well among the relatively well-educated, affluent, politically active audience that tunes into C-SPAN's offerings.

"It is obvious that C-SPAN viewers are mature enough to take us warts and all and that we have survived that scrutiny," he said with what appeared to be a sigh of relief. "Perhaps they have learned that the modern filibuster does not resemble the portrayal in the movie 'Mr. Smith Goes to Washington.' Perhaps they have learned, as I have, more than they wanted to know about the nondebatable motion to proceed during morning hour {which occupied the Senate for most of one day last month}. But the comments that they have called into the network . . . have been valid. When we are good, they like us, and when we are bad, they like us because we are the real thing."

The Senate has neither "conned nor dazzled the American people," Byrd added. "They see us as we are. We are not perfect, but we seem to be perfectly acceptable."

As for television's impact on the Senate, Byrd said a study of Senate proceedings in 1979, 1985 and the first part of this year by James Thorndike, the Senate Journal clerk, indicated little change in time consumed by recesses as opposed to the conduct of legislative business. Time spent on speechmaking has remained relatively constant. In a major change, the Senate has cut by more than half the amount of time spent in quorum calls, which are often used to mask the fact that the Senate doesn't know what to do next.

"My fears did not materialize," said Sen. J. Bennett Johnston (D-La.), who had opposed televising the Senate but now thinks it has been beneficial. "Senators, mindful of the prying eye of television, are not talking as long as I feared," he said. "They may speak more often, but they're a little more succinct."

Mainly, he said, television has not undermined the fundamental goals of the Senate that date back two centuries, including its role in cooling the passions of the moment and protecting minority viewpoints. The Senate, he observed with some relief, remains "as messy as ever."