Hoffa is withholding a presidential endorsement until after Labor Day, when it will have the results of an endorsement survey in its July/August magazine.
The decision could be very important to the election. The Teamsters is the largest union in Ohio, Pennsylvania and Illinois, which have 66 electoral votes - about a quarter of the number needed to win.
Hoffa is meeting today with the president of the United Auto Workers, which also has so far refused to endorse a presidential candidate.
Republicans said that Hoffa just being there was a victory of sorts. "Just think how George Bush would feel if the Christian Coalition were sitting down with Al Gore right now," Rep. Peter King of New York told MSNBC.
"I didn't know I had so many Republican friends," Hoffa told a cheering crowd, according to published reports.
The reception was hosted by several Republican elected officials, including Sen. Ben Nighthorse Campbell of Colorado, Sen. Orrin Hatch of Utah, Sen. Rick Santorum of Pennsylvania, Rep. Tom Davis of Virginia, Rep. Peter Hoekstra of Michigan and Gov. Tom Ridge of Pennsylvania.
Campbell holds a CDL and was supportive of independent truckers who convoyed to the capital earlier this year to protest high diesel fuel prices. Michigan Teamsters earlier this year endorsed Hoekstra because of his support for ending the federal government's 11-year supervision of the union. Santorum and Hatch have also expressed support for lifting federal supervision.
Hoffa will be a delegate to the Democratic National Convention in Los Angeles Aug. 13.