MDM seems to be looking for specific evidence of legal collusion, so let's review what we know.
The Russian government attempted to interfere with and undermine American democracy. Donald Trump's campaign knew this was happening, and gave both explicit consent and public endorsement of this process. Campaign staffers met secretly with Russian intelligence operatives on multiple occasions, to discuss how they could establish a quid pro quo with the Russians for their help with the election, for example by lifting sanctions, changing the GOP platform plank about Russia, and establishing secret backchannel communications to avoid US intelligence monitoring. These compromised campaign staffers were then appointed to positions of power in the US government that required security clearances, and they lied to security investigators and concealed their foreign contacts, sometimes in front of the US Senate, in order to hide their complicity.
The national security advisor (Flynn) was forced to resign over these lies. The campaign manager (Manafort) was forced to resign because he was literally being paid by the Russians to advance Russian interests, and subsequently had to register as a foreign agent. The white house senior advisor (Kushner) was recruited by Russian intelligence, agreed to circumvent official protocols in order to assist Russia, and is now under investigation. The Attorney General (Sessions) lied to congress about meeting with the Russians and had to recuse himself in order to save his job.
None of that is evidence of collusion by Trump, personally, so it basically won't affect him if he just fires all of those people.
But we also know that Trump had received millions of dollars from Russian oligarchs closely tied to Putin, ostensibly as "investments" in failing real estate deals. These look like bribes, but are probably legal. There is no law against accepting ridiculous sums of money from Putin for items of nominal value.
And we know that Trump knew about the Russian hacks of the DNC, but so far we don't have any public evidence that Trump or his campaign assisted in the release and dissemination of that information, like on Facebook, other than making public statements that it should be leaked.
And lastly, Trump publicly admitted to obstruction of justice. He said he tried to squash the Russia investigation internally, and then fired FBI Director Comey over it when he wouldn't do it. That's about as clear cut of a case as I think can be made.
The Trump Jr. meeting in which he solicited opposition research on Clinton will probably warrant a fine but no jail time. It's illegal, but not very illegal. More importantly, it demonstrates that the campaign was actively seeking to collude.
And in the middle of all of this, while Trump continued to deny any connection with the Russians even as six of his top staffers admitted to it, Trump invited the lead Russian spy in the US for a private meeting in the Oval Office. That was a pure troll move, I think, designed to send the clear message that he considers himself above the law. It was "I could shoot someone in the middle of 5th Ave and get away with it" all over again.
So what else do we really need? What additional forms of collusion would reach the legal threshold required to convict of collusion?
And for the record, comparing this list to the birther conspiracy is laughably absurd. There was never any evidence to support that theory other than "he's black" and it was promptly and completely debunked right up front. There was no long list of high level staffers being fired over it. Nobody ever had to admit any part of it was true after lying about it to congress and federal investigators. No foreign government ever confirmed it. It's fine to ask for evidence, but let's not pretend that the evidence of Russian collusion is as non-existent as was the evidence for Obama being born in Kenya.