No one in this thread seem to be aware that "Jewish homeland" started to form under the Ottoman Empire IOTL. First (proto-) Zionist settlers (Bilu) started to immigrate in 1880s. By the 1914 there was about 50-70,000 Jews in Palestine, if my memory serves me well. Rishon Letzion, Tel Aviv and number of smaller towns were founded, as well as number of agricultural settlements, fruit plantations, wineries etc. Yishuv (Jewish Community) even started somewhat along the lines of (highly informal) program to build up a cadre of Ottoman-educated elite. Moshe Sharet went into Ottoman university, and I believe Ben Gurion too (or prepared to do so). So continuing existence of Ottoman rule ITTL is by no means an unbreakable barrier for the Jewish settlement movement.
IOTL Ottomans never had a consistent policy toward Zionist experiment. Having weak government and being busy in other areas (Yong Turks revolution, war with Italy, Balkan wars), they largely ignored the phenomenon. Dealing with Jews was mostly business of local (very corrupt) authorities. However, Young Turks (especially their Donmeh members, like Mehmet Cavit Bey) were big on transforming Islamic empire into a secular state which benefits from effort of it's citizens regardless of ethnic or religious affiliation. So I see absolutely no reason why Ottomans should automatically bow to fanatical illiterate sheikhs (utterly despised by Istambul IOTL) and kill Jewish settlement effort. So, it comes down to 2 questions:
1. How would Zionists get land?
2. How would Zionists get peoples to settle on the land?
It is very easy to get an answer for 1st questions. They'll buy the land. Every piece of dirt which belonged to Yishuv pre-1948 had been bought and paid for in cash. Jews might do it under Turks post-1914 as they did it under British post-1918 or Turks pre-1914 IOTL. It is the second question which would be a problem. IOTL most pre-1914 immigrants kept it's original (Russian, Austrian, German, French, Romanian) citizenship, using pretty relaxed pre-WWI Ottoman policy which allowed foreigners to live and do business there. Nobody guarantee that Ottomans would keep it this way in much more claustrophobic post-WWI world.
However, unlike British IOTL, Ottomans has a very solid economic and political reason to encourage Jewish immigration ITTL. They have to modernize and industrialize the Empire in order to survive. They need factories, mines, railways, oilfields, pipelines, widespread phone and telegraph network. And, to do all that, they need literate workforce to build and operate "stuff". And they don't have nearly enough literates within the Empire. So, for them an influx of literate and urban Jews, ready and willing to take industrial jobs, might be a gift from Heaven. Therefore, looking at whole situation from Istanbul, authority need to find a good balance between getting a workforce they desperately need and keeping illiterate Arabs quiet. I'm not saying that Turks will definitely tilt toward encouraging immigration, but they might. So, instead of less immigration pre-WWII we might see more ITTL comparing with OTL. I would not be surprised if some important components of nascent military-industrial complex of Ottoman Empire will spring up in Haifa or Tel-Aviv - Yaffo. Stuff like plane engine factory or armoured car assembling facility. Or airplane works. Why not? Where else within the Empire can you get enough workers who know how to operate XX-century machinery?
And now a million-dollar question. Would Israel come into existence ITTL? I honestly don't know. It will depend on general survivability of the Ottoman Empire. There's a good chance that decolonization process would kill it, but there's also a chance that it would be less of "colonial empire" and more of "multinational state" by that moment. However, if the Empire breaks up and it carried the "pro-emigration" policy I described above (i.e. if there're several hundred thousand Jews in the Palestine by that moment, I honestly don't know how would you prevent them from declaring Israel).