The speculation proves true:

Kennedy confidantes told the Globe today that the Bay State's senior senator will appear with Obama and Kennedy's niece, Caroline Kennedy, at a morning rally at American University in Washington tomorrow to announce his support.

That will be a potentially significant boost for Obama as he heads into a series of critical primaries on Super Tuesday, Feb. 5.

Kennedy believes Obama can ``transcend race'' and bring unity to the country, a Kennedy associate told the Globe. Kennedy was also impressed by Obama's deep involvement last year in the bipartisan effort to craft legislation on immigration reform, a politically touchy subject the other presidential candidates avoided, the associate said.

The coveted endorsement is a huge blow to New York Senator Hillary Clinton, who is both a senatorial colleague and a friend of the Kennedy family. In a campaign where Clinton has trumpeted her experience over Obama's call for hope and change, the endorsement by one of the most experienced and respected Democrats in the Senate is a particularly dramatic coup for Obama.

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