Democratic presidential candidate Bernie Sanders said Sunday that former New York Mayor Michael Bloomberg potentially entering the White House race shows that the wealthy are too “controlling” of American politics, offering perhaps the most critical assessment within the 2016 field of a Bloomberg bid.

“What I have been saying for a long time is that this country is moving away from democracy to oligarchy, that billionaires are the people who are controlling our political life,” he said on ABC’s “This Week.”

Still, Sanders, whose campaign is a champion for the middle class and poor, expressed confidence about winning the presidency in a matchup with billionaire Donald Trump as the Republican nominee and billionaire Bloomberg as a third-party candidate.

“That is not what, to my view, American democracy is supposed to be about -- a contest between billionaires,” the Vermont Independent senator said. “If that takes place, I am confident that we will win it.”

Bloomberg, an Independent and successful businessman, has asked advisers to draft a game plan. And he plans to commission a poll after the Iowa and New Hampshire primaries in early February before deciding on a run, as reported first by The New York Times.

Bloomberg seems to suggest he’d enter the race only if Democratic front-runner Hillary Clinton loses the party nomination to Sanders. And he has reportedly told associates that he would spend $1 billion of his own money on the race.

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I’m going to relieve him of that and get the nomination so he doesn’t have to,” Clinton said on NBC’s “Meet the Press.”

Trump said on the same show: "I would love to have Michael Bloomberg run. I would love that competition. I think I'd do very well against it."

Also on Sunday, Republican presidential candidate Marco Rubio largely dismissed a Bloomberg candidacy.

“Right now, he’s just a public citizen who owns a company,” said Rubio, who implied he has no problem with Bloomberg’s wealth, then retold his personal journey. “I think this is a great country where the son of a bartender and a maid can be running for the same office and have the same opportunity as the son of a millionaire. … I want America to remain that kind of country.”   

GOP candidate Jeb Bush, raised in an affluent family and whose father was president, called Bloomberg a “great mayor,” despite have different political views.

“Look, he’s a good man,” Bush also said on ABC’s “This Week.” “He’s much more liberal than I am, but he’s a good person.”

Bush also predicted that the 73-year-old Bloomberg won’t get into the race unless the general election features the front-running Trump and Sanders, who is second behind Clinton in the Democratic primary race.