But the unusual way in which the former defense secretary ended up at Mr. Bush's side at a news conference here on Tuesday to announce the vice-presidential selection has stirred concern among some Republicans.

Party leaders rather than presidential candidates continued to make vice-presidential selections to balance the ticket, often choosing someone from a different party faction who was not personally close to the presidential nominee.

There is talk, officials said, of Mr. Gore's announcing his vice-presidential selection in early August to cut into the momentum that Mr. Bush is expected to receive from the Philadelphia convention, which begins on July 31.

The release came at a time when it was likely to be overshadowed by the impending news of Gov. George W. Bush's vice-presidential selection, but a White House spokesman denied any connection.

The weakened Nixon did not want a fight for the vice-presidential selection.

Indeed, though naturally parrying questions about a vice-presidential selection, Mr. Bush certainly does nothing to rule anybody out.

They noted that because President Bush had such a long, varied and prominent political career, many of his son's prospective vice-presidential selections had ties to him.

Chatting with reporters outside a fund-raiser here, Ed Rendell, chairman of the Democratic National Committee, suggested that religion could be a factor in the vice-presidential selection.

Mr. Bradley's endorsement also marks a shift toward the convention season and the vice-presidential selections.

Long's involvement with the federal anti-poverty program in Louisiana led to his close friendship with U.S. Senator George McGovern's vice-presidential selection, R. Sargent Shriver, an Illinois native and a brother-in-law of the Kennedys.