Manchin said the letter was an embarrassment to the Senate.
Manchin is not the only senator who has been interviewed in Trump Tower, however. Sen. Heidi Heitkamp (D-ND) was also floated to serve in Trump's cabinet. She went to New York City to interview earlier this month. But Reid said he was not convinced Heitkamp was interested like Manchin was.
"I don't think she'd do that," Reid said of Heitkamp leaving the Senate.
Reid–in a kind of shot at Manchin– divulged how hard Democrats had been trying to convince Manchin not to leave.
"Listen, I know that we've done stuff in the last few weeks to try to make Manchin happy," Reid said.
Last week, Senate Democrats rallied around Manchin as he tried to extend health care benefits for coal miners. Manchin's fight kept Democrats in Washington longer than expected and forced the Senate up against the clock as it tried to advance a must-pass spending bill.
"Joe Manchin is obviously running for a cabinet spot," Reid said again.