No they don't. Russia's performance in the 1877 war was abysmal, and many on the forum have noted that they could have easily lost if not for some unlucky moves from the Turks. But even given that they win, I don't think Russia has the strength to push all the way down to Kostaniyye; again, based off of their abysmal performance in the 1877 war.
Can we just put this bullcrap to rest once and for all?
Russia, with its inferior arms procurements, without western allies, with no blue-water navy, and at best a numerical parity throughout most active theatres, managed, on the offensive at all times, to overcome a well-supplied, well-entrenched, well-armed Turkish army supported by a sizable navy, which was defending across rivers and mountainous passes from some truly magnificent defensive positions - while incurring less casualties, and ending the war in Adrianople and looking at the walls of the enemy capital itself.
This is not to say the Ottomans couldn't have won, there's lots of ways in which they could have done better, and maybe should have. But historically, they got absolutely smashed, curbstomped, flattened, overrun, etc. by an inferior force aided by volunteer militas, and basically had to be saved by their European allies through diplomacy.
The Crimean war was far more of a Russian victory than 1878 was for Turkey, to put it plainly. Japan's outstanding performance in 1905 was actually less lopsided in their favour than Russia's abysmal performance in 1878. That's the benchmark we are talking about here.
I have no idea what makes people say that 1877/78 was a close run thing. It was not. Turkey should have done better, yes, but it turned out to be a complete disaster for them, and that's all there is to say, really.
And yet people just keep repeating how the Ottomans "almost won":
here and
here for example.