Money talks.
Check it out:

President Obama has not taken long to signal just how Thad Cochran will repay the debt for the quarter million dollar campaign donation from anti-gun Michael Bloomberg. A renewed push for gun control is on the horizon, and Obama is expecting great things from Bloomberg and his new anti-gun group. Now that he has a senior statesman in his hip pocket they expect to have greater success in their effort to push measures like background checks.

Obama’s attempts at gun control were defeated in 2013,

“Since legislation has been controversial for some time, I thought that this was going to be a breakthrough moment, [the Sandy Hook Shooting]” Obama said. “It was probably the most disappointing moment I had in dealing with Congress.”

Bloomberg is not stupid nor do I expect he is willing to waste his money. The donation to Cochran did not come because Bloomberg thought Cochran was a great guy.