Candidates and committees in 2013 paid Romney’s still idling campaign at least $675,000 to rent his fundraising lists, while prospective presidential candidates like Scott Walker and Chris Christie have cozied up to Romney’s fundraisers and donors in closed-door meetings and fundraisers. Romney himself quietly slipped into Manhattan in December to headline a big-donor dinner for the Republican National Committee, where he was a huge hit, sources tell POLITICO.

And last month, Romney, for the first time as an ex-candidate, signed a fundraising letter sent to the Romney for President national direct mail list on letterhead bearing Romney’s name asking for contributions to another candidate — his 2012 vice presidential pick, Wisconsin Rep. Paul Ryan, who is often mentioned as a possible 2016 contender…

“Mitt has been courted by lots of folks from the day we lost. People up and down the ticket have asked if he would he do a letter, an email or an event — or if Ann would — and that’s only increased exponentially as buyers’ remorse has set in,” said Kaufman. “He could fill every day, every night three times over. And, that’s only going to expand headed into 2016. Not just on the money side, but Mitt has a huge network of friends at all levels that have been helpful to people.”