(The following is based on a talk given by the renowned author and speaker, Rav Ezriel Tauber, founder of Shalheves.)
Why should we be capable of bringing Moshiach? The generation of the midbar, who saw Kriyas Yam Suf and actually heard Hashem speak, didn't bring Moshiach. Neither did all the great prophets, tanaim, amoraim, gaonim, rishonim, acharonim and all the other tzadikim of previous generations. And WE, in this day and age, are supposed to bring Moshiach? How is that?
As an example, imagine the city of Tzfas, less than five hundren years ago. The place was a "who's who" of the some of the greatest and most famous tzadikim in our history.
The Posek was the Beis Yosef, R' Yosef Caro, who wrote the Shulchan Aruch.
The great teacher of Kabbala was the Holy Arizal.
The preacher was the Alshich HaKodosh.
The chazzan was R' Shlomo Alkabetz, the author of Lecha Dodi.
The shamas of the shul was R' Elazar Azkiri, who wrote Sefer Chareidim and the famous song, Yedid Nefesh. Imagine, even the one who took care of the menial tasks in the Shul was such a great tzadik.
These are just a few; the list could go on and on, as there were numerous great tzadikim in Tzfas at that time. All these great tzadikim, among them the greatest Poskim, Talmidei Chachomim, and Kabbalists, couldn't bring Moshiach, and we are actually supposed to believe that we can?
Imagine if you found a way to turn silver into gold. That would be very valuable. Now, imagine you found a way to turn copper into gold. That would be an even neater trick and, of course, would be much more valuable. Imagine turning aluminum into gold. Now, imagine turning dirt into gold or even if you could only turn that dirt into silver. Obviously that would really be very valuable, as you are taking something with no value and turning into a precious metal.
Similarly, if we work on ourselves, corresponding to the dirt, as opposed to the previous generations, corresponding to silver, copper or aluminum, it is a lot more valuable when we improve ourselves. Let's take one issue no one ever had the streets that we have today; in one day we probably see more promiscuity than previous generations saw their whole life. When we control what we see or overcome any of the great temptations that are so prevalent in the world today, we bring great pleasure, so to speak, to the Ribono Shel Olam. (See previous post on Shmira Einayim) Our "simple acts" are potentially more valuable in Shomayim than that of much greater people of the past. In line with this, tzadikim of the past have said that the "simplest" mitzvas that will be done by simple Jews in the future will be worth more than the mitzvas done by tzadikim of their time.
So the answer is YES, we can indeed bring Moshiach, and we should always keep that in mind. May he come speedily in our days. Amen.