The American people were well represented by the close-to-unanimous majorities renewing the Voting Rights Act in both houses of Congress. President Reagan echoed their ideals - and his own words of last fall - when he hailed last week's 85-8 Senate vote as a bipartisan message that no American's vote shall be ''defiled, diluted, or denied.'' The House, which had voted 389-24 for a somewhat stronger bill, was expected to accept the Senate compromise version. Thus the keystone of United States civil rights legislation was free at last from trimming and filibustering long before the August deadline for expiration or renewal of a central provision.
This is the so-called preclearance provision. It requires that all or part of 22 states with a history of voting discrimination seek federal approval of any proposed changes in election procedures. The requirement is extended for 25 years under the new legislation.
The challenge now is for voting rights to be so universally maintained and protected that another extension will not be needed. Jurisdictions must resist the temptation to redraw districts or switch to at-large voting, for example, when these ''defile, dilute, or deny'' minority votes.
Up to now the necessity for safeguards against such devices has not diminished. As of 1981 some 800 proposed electoral changes had been objected to by federal authorities since the law was passed in 1965. More than half of these came up in the past five years.
Meanwhile, thousands of proper electoral changes have been federally approved. It is estimated that a quarter of the preclearance jurisdictions have mended their ways so thoroughly that they could qualify right now for the new law's ''bailout'' provision. This relieves jurisdictions of preclearance when they can show a history of 10 years without discrimination and with definite efforts in behalf of minority voting participation.
There is no reason that any place in the country should not bail itself out. The right to a free and fair vote is the fundamental civil right. It provides a peaceful channel for affirming other rights.
To prevent backsliding, all election jurisdictions, not only the preclearance ones, are covered by the new legislation's valuable clarification of congressional intentions on how violations are to be proved. The situation had been complicated by Supreme Court interpretations that ''intent'' to discriminate had to be found. Some members of Congress wanted to lock in this interpretation and rule out discriminatory ''results'' as proof of violation. The compromise was to recognize the ''results'' criterion but specify that it depend on ''total'' circumstances - such as residency requirements and registration procedures - and not only on election outcomes.
The upshot was that even such a former opponent as Sen. Strom Thurmond voted for passage. President Reagan was said to have lost points with civil rights groups by failing to have endorsed a strong bill sooner. But he can ease any such handicap by backing his Justice Department in firm enforcement of the law he has now joined in supporting.
In short, just when the steam seemed to be going out of congressional and adminstration commitment to civil rights, the bipartisan rededication to the Voting Rights Act is a reminder that the steam is still there to be tapped.