Astrology is the light that eliminates darkness of ignorance. Astrology in itself is a challenging subject without the proper information. Mostly I stay away from political predictions due to the lack of reliable birth data 

Is it impossible to predict without birthdate? No there are a lot of alternative techniques one of them is interpreting horoscopes by taking the moon as Lagna though the moon stays in a zodiac for 2 and half days studying horoscopes using the moon Lagna unearths a lot of facts. There are a lot of cases where yogas in a horoscope have worked well with respect to the moon and individuals have reached greater Heights when the dasa of a planet well placed from the moon runs for individuals. Gaja kesari yoga,chandradi works well and provides fruitful results The next possible option in case of inaccurate birthtime is using prashna kundli involves preparing a horoscope at the time of query and predicting future 

Here are some ways:

There are a lot of astrologers who have excelled in prashna kundli like KP astrologers. Even if there is a proper birth time checking query using prashna Kundli reinforces a lot of facts Prashna Kundli technique has yielded 70% success or more in many cases. In prashna kundali lagna and lagna lord place, an important role and afflicted lagna and lagna Lord shows misfortune for the querist 

The specific query like education, marriage,own house, profession,business we have to study related houses like 10th House for profession, 7th house for business, 4th house for property and so on and so on.

Some astrologers do face reading and there is also anga shastra where we study and predict using body language. 

another important technique we can use is palmistry. Palmistry is the predicting using lines of our palm. For men right palm is seen and for females left palm has to be seen. There are some great astrologers who can construct horoscopes using palm reading great by raman is one of them 

The great kn raoji used rectify birth using charas and predicted wonderfully even incase if lost horoscopes 

Another important technique is birth time rectification. There are a lot of techniques available for birth time rectification like the tattva method etc 

So i conclude by saying lack of reliable birth time is definitely a handicap but there are lot of alternatives like palmistry, using moon sign, prashna shastra using which we can predict accurately.