"I WAS really impressed," a Law School politico said last week after talking with U.S. Senator William B. Spong Jr. (D-Va.). "I never realized a Southern politician could be articulate."

Despite his marked eastern Virginia drawl, Spong's knowledgeable discussions of the South's economic growth and Virginia's rapid urbanization show that he is quite different from the rural bosses who built their power in the South on segregation, economic stagnation, and a restricted electorate. The freshman Senator likes to emphasize his break with traditional Southern politics by exclaiming, with feigned astonishment and a trace of pride, "Why, did you know that I'm the first Virginia Senator ever elected from a city?"

Spong, who lives in Portsmouth, rose to prominence as the leader of the urban bloc in Virginia's General Assembly. For 30 years the late Sen. Harry F. Byrd's Organization dominated the state's politics, with the only opposition coming from the small Progressive wing of the Democratic Party. But within the last 10 years a band of moderates, consisting of representatives from Richmond, the urban areas of Northern Virginia, and Tidewater cities like Norfolk and Portsmouth has sprung up between the two extremes in the party.

Like most of the moderates, Spong is a middleaged, socially prominent lawyer. He graduated from Hampden-Sydney College, where his friends included the sons of three past Virginia governors, and then went to Europe with the 8th Army Corps during the Second World War. After the war, he studied law at the University of Virginia and at the University of Edinburgh. In 1954 he won election to the state's House of Delegates and two years later entered the State Senate. While he was in the Senate, he earned acclaim even from the Byrd people for a four-year study of the state's public education system.

AFTER a decade of working with the Organization in the legislature, Spong decided to challenge it in a state-wide contest. Projecting the image of an attractive young problem-solver, he entered the Democratic primary in July, 1966, in an effort to wrest the nomination away from veteran Sen. A. Willis Robertson. Although he was helped by abolition of the poll tax and the subsequent growth in the Negro electorate, Spong's most active support came from a whole generation of young voters who could not identify with the old men in the Organization. Robertson conducted the best-financed and least imaginative campaign Virginia has ever seen, while for the young voters in the state, even Spong's striped ties reinforced the images the two men presented. Spong outpolled Robertson by just 611 of the nearly 450,000 votes cast, but he easily defeated his Republican opponent in the November election.

Spong's first year in office, however, has disappointed Virginians who hoped for a bold new era in the state's politics. He has worked as conscientiously as everyone expected--his large, cheerful, busy staff is most unusual for a Virginian serving in Washington--but on 83 per cent of the Senate votes he has agreed with the state's senior Senator, Harry Byrd Jr.

Spong defends his seemingly conservative voting record by pointing out that most Senate votes are routine and that he has opposed Byrd on several important rollcalls. Their most notable splits have been over confirmation of Justice Thurgood Marshall, ratification of the Soviet consular treaty, raising the debt limit, and keeping Head Start in the poverty program.

ALTHOUGH Spong has voted with the Southern bloc on tactical moves concerned with the civil rights bill now pending in the Senate, he hopes to cast the South's first vote for passage of a civil rights measure, but only if the open housing provision is deleted from the bill.

"Open housing ought to be a local matter," he says. "That's exactly what I said in my campaign, and I even said it directly to the Crusade for Voters." The Crusade is a powerful Negro political organization, whose energetic support was invaluable to win the primary. Spong's supporters use incidents like this to illustrate his remarkable candor. His desire to "tell people the truth about these things" has also led him to disclose publicly the sources of his campaign financing and his personal assets.

Visiting constituents who admire this forth-rightness occasionally point to his voting record and suggest that he should have widened his viewpoint after a year in office. But the Senator tells them, "I can't be what I'm not. I'm not a doctrinaire liberal anymore than I'm a doctrinaire conservative." He considers himself "just a normal 47-year-old lawyer." The General Assembly was "really just a recreation for me--I practiced law very hard then," he says of his earlier political career.

He evidently wants people to think that he isn't a politician at all. Anyone who meets him is impressed by his low-keyed good nature and with what could be an almost deliberate effort to be unpretentious. Spong seems to enjoy telling stories about the Senate or about his campaigns in Virginia more than analyzing his role in changing the political structure of the state.

"I've never been active in party committees or conventions or anything like that," he says. His preference for legislation over political organizing reflects his view of himself as a lawyer rather than a politician; of course, it also testifies to the Byrd Organization's complete control of state Democratic machinery. Although Spong clearly represents a new political movement in the Old Dominion, National Committeeman Sydney Kellam, who has long been the Organization's chief strategist, still symbolizes Virginia Politics to Lyndon Johnson and his aides.

AS a Senator, Spong also considers his role to be legislative rather than political--"I've been keeping quiet and trying to do a good job on my committees, especially since they're dealing with things like highways and pollution that are important to urban areas."

His quiet devotion to Senate chores gives him a handy excuse for staying out of Virginia's political struggles at a time when the Organization still controls county governments, the state legislature, and the governor's mansion. Last summer his allies soundly defeated Kellam's brother in a primary race for the State Senate, but he says, "I didn't do anything--I've set off a movement that will keep growing whether I do anything or not." The young lawyers who helped in his 1966 campaign are planning to move into politics for themselves, and "I couldn't stop them if I wanted to," Spong says.

One of the major questions in Virginia is how soon Spong will join the battle to elect the progressive leaders the state needs to cope with its emerging industrial and urban character. Despite his natural tendency to stay aloof from day-to-day political maneuvering, he feels that "this is something I can't just walk away from." It seems likely that in one or two years, after he has established himself in the Senate, Spong will take a much more active interest in "party committees and conventions"--as well as elections.