DES MOINES, JAN. 24 -- The latest polls of likely Democratic voters in Iowa and New Hampshire show Gary Hart, who reentered the presidential race just before Christmas, fading dramatically.

Rep. Richard A. Gephardt (Mo.), Massachusetts Gov. Michael S. Dukakis and Sen. Paul Simon (Ill.) are virtually tied in Iowa and Dukakis is leading in New Hampshire.

The latest Iowa Poll of likely Democratic participants in the Feb. 8 precinct caucuses showed Gephardt the choice of 19 percent, Dukakis with 18 percent and Simon with 17 percent. Hart was fourth with 13 percent, followed by Jesse L. Jackson with 11 percent, former Arizona governor Bruce Babbitt with 10 percent, Sen. Albert Gore Jr. (Tenn.), who wrote Iowa off and stopped campaigning here, with less than one percent and 12 percent undecided.

A Los Angeles Times poll of Democrats in New Hampshire showed Dukakis with a substantial lead.

Hart's surprising and dramatic reentry into the presidential race made him the front-runner in an Iowa Poll taken immediately after, and he made a strong showing in the polls in New Hampshire.

Many political observers said they thought that Hart's strong showing in the polls would subside, as it has.

The Iowa Poll revealed considerable tolerance for Hart's private life -- he dropped out of the race after a sex scandal last May -- but strong reservations about him as a presidential candidate.

Fifty-eight percent of likely Democratic caucus participants said they didn't think his personal life would affect his performance as president. However, 47 percent said he is not a person they can trust, about half -- including 30 percent of his supporters -- think he has hurt the Democratic Party and only 26 percent thought he was bringing fresh new ideas to the campaign.