REUTERS/Carlo Allegri
Donald Trump speaks at a campaign event in an airplane hangar in Rome, New York April 12, 2016.
Speaking to The Financial Times' Stephen Foley, Gundlach - CEO of DoubleLine Funds - said if Trump wins the Republican nomination he will win the presidency.
On the day Trump announced his nomination, Gundlach told DoubleLine staff that "the greatest long in the entire world" was a bet Trump wins the presidency, according to the FT.
When Trump announced his bid he was 53-to-1 to win the presidency; Trump is now about 6-to-1 to win, according to Betfair. So, it's been a pretty good long!
Using bond market lingo, Gundlach called Trump "the unconstrained bond fund of the political arena."
Unconstrained funds allow managers to buy almost any kind of fixed income asset - instead of a traditional fund which has strict allocation requirements based on duration and credit profile - thus giving investors a potential for larger returns but the certainty of less clarity on what the fund will own.
In this way, Trump, like an unconstrained bond fund, can be one thing in the morning and something else in the evening, a phenomenon the political press now knows all too well. Notably, Gundlach's bond rival Bill Gross runs an unconstrained fund at Janus.
Trump is expected to win the New York primary on Tuesday, potentially in a landslide.
However, despite his lead in both the polls and the delegate count, the prospect of a Trump nomination has become increasingly imperiled as the Republican party has begun setting in motion the wheels to pull Trump-pledged delegates elsewhere if he doesn't have 1,237 pledged delegates by the convention.
But the machinations of delegate haggling are not the concern here.
The point is that Gundlach - one of the most followed names in financial markets - thinks we are close, very close, to seeing Donald Trump in the White House.