WASHINGTON -- Senate confirmation of President Bush's choice to be U.S. ambassador to the European Union has been delayed for several weeks, and the nominee may not take his post until well into November. Bush's choice as U.S. ambassador to the United Nations is serving under a recess appointment and may never be confirmed. The reason: the individual whims of two Republican senators.

 Freshman Sen. Mel Martinez of Florida last week temporarily blocked the confirmation of longtime Republican stalwart C. Boyden Gray to the EU for petty political reasons. Much more serious because its effect looks permanent, Sen. George Voinovich of Ohio at the same time stiffened his opposition to John Bolton at the United Nations. He apparently swallowed whole the Democratic campaign of personal destruction.

 The 17th-century Polish institution of the liberum veto, where objection by one deputy in Poland's Diet could defeat any proposal, lives in spirit in today's U.S. Senate. Under arcane Senate rules, Martinez was able single-handedly to block Gray's confirmation. Because of the polarized party split, Voinovich alone is able to limit Bolton's term to the end of the current Congress. The pity is that both Gray and Bolton are well qualified with long records of government service in Republican administrations.

 Gray, a prominent Washington lawyer who has been an aide to Ronald Reagan and George H.W. Bush, was expected to sail through an Oct. 5 "business session" of the Senate Foreign Relations Committee as one of 20 routine diplomatic nominees. But Martinez objected to Gray, sidetracking his confirmation. Martinez did not have to give a reason, and he did not.

  "It was personal," a Martinez aide told me. The senator, normally accessible, declined to talk to me about his reasons. He obviously was reticent because the "personal" reason was political revenge. Gray last year publicly withdrew his support in the Republican primary from Martinez, a former trial lawyer who had resigned as secretary of Housing and Urban Development to run for the Senate. "We simply do not need any more Republicans who oppose tort reform in the Senate," Gray said then.

 Martinez won the primary despite Gray, but he obviously has not forgiven or forgotten. According to Martinez's office, he met with Gray after the committee session, and they settled their differences. It was too late for Gray to join the other 19 diplomatic nominees to be confirmed by the full Senate without debate Oct. 6. No new committee "business session" is likely until early in November.

 The effect of Martinez's mischief at least is only temporary, in contrast with Voinovich fully joining the Democratic vendetta against Bolton. Voinovich, a two-term senator after serving as mayor of Cleveland and governor of Ohio, let it be known last week that he was changing his vote from "present" to "no" on Bolton. That means the nomination will not even get out of committee to face a filibuster on the Senate floor. That rules out even bringing up Bolton's renomination in committee.

 Voinovich's problems with Bolton began last May when he wandered into a Foreign Relations Committee hearing and swallowed whole Democratic deconstruction of Bolton orchestrated by Sen. Christopher Dodd. The White House had expected any Bush U.N. nominee to face confirmation trouble prior to the 2004 election. But the president named John Danforth, a prestigious former U.S. senator, for a five-month U.N. stint to avoid a campaign deluge. Bolton's long record of criticizing Fidel Castro made him a special target of Dodd, a champion of "normalizing" U.S.-Cuban relations.

 But why did Voinovich heighten his opposition? Serving under a recess appointment, Bolton has gotten high marks at the United Nations, as he has in previous government positions. One old hand in the U.S. Mission at Turtle Bay told me that while Bolton can be "blunt," he is smart, very well informed and faithfully follows instructions from Washington.

 Voinovich declined to talk to me about why, in the face of that record, he has lowered his opinion of Bolton. Fellow Republican senators who have asked him have received no explanation. Being a U.S. senator means never having to explain yourself. No wonder respectable citizens flinch at accepting a job that subjects them to senatorial mercy.