How can an undergraduate TA ask to give a lecture if they have given one in the past?
My first reaction, if a TA or GTA asked to give a lecture, would be to worry about the time.  Almost every undergrad math class is in a rush to cover the material.  At the end of almost every course, almost every math lecturer is wishing for another day or two.  And you want one of my precious, precious days?  Even if you do a really swell job, you might leave some loose ends, which I have to spend 5 or 10 minutes the next class polishing up. Then I have to cram that day's 50 minutes into 40 minutes.   I say this so you know what you might be asking.

The second thing is that, depending on your location and school, there may be rules about who can teach at what level.  In Texas, there are laws (from the state legislature) which say that a master's degree can teach math classes only up to a certain level.  And that a grad student can teach classes only up to a certain level.  And some schools advertise things like, "All classes are taught by professors."  So you might run into a rule or law that simply prevents you from lecturing in a non-emergency situation.  

Having said that, I don't see any problem with you approaching the professor and saying that you would like more experience lecturing.  You understand there are hurdles, but if possible, you'd like to do another lecture.