Bloomberg was a democrat before he became an independent. He was an independent before he became a republican. If he thought it would get him a vote,Bloomie would be a martian. The only thing he really is , is a hard core leftist.
You've got the order wrong.
He was a registered Democrat before he ran for office.
When he ran for Mayor, it was as a Republican. He also got the endorsement, and ballot line, of the Independence Party of New York.
The second (and third) time he ran for Mayor, he switched his registration to the Independence Party of New York - but remained the Republican Party candidate as well, keeping their ballot line and getting their endorsement.
All three times, the Democratic Party opposed him, and all 3 of his major challengers have come from
the left.
Calling Bloomberg a "liberal" or a "leftist" doesn't make sense when the "liberals" and the "leftists" were the
only ones running against him.
He's moderate on social issues, but fiscally, he's decidedly right of center.