Update: Voting is now closed. See who won!

Previously: So we’ve had a lot of fun voting for our favorite public radio shows. But this is where it gets real. And we’ve even got a prize.

In Round 4, “Radiolab” knocked out “Fresh Air,” and in a nailbiter, “This American Life” clawed its way to victory over “Wait Wait… Don’t Tell Me!” Out of 71,507 votes cast, “This American Life” drew the victory by only 665 votes, giving them a margin of victory of less than 1 percent.

Now “This American Life” and “Radiolab” face off in the arena. Can Ira Glass and the contributors of “This American Life” take out the tag team of Jad Abumrad and Robert Krulwich from “Radiolab”?

To help you make your decision, check out these links to the most recent full episodes (as of press time) of both shows:

You can also listen to a selection of the best “Radiolab” episodes and the best episodes of “This American Life.”

A couple of my personal favorite segments: “Opening Night” from “This American Life,” and “On Repeat” from “Radiolab.”

Watch “This American Life” host Ira Glass talking about what makes a good story:

And check out Jad Abumrad from “Radiolab” on the power of sound in the world of science:

OK, are you feeling educated? Great. Now it’s time to exercise your public radio democratic duty and vote for the grand champion.

Voting closes Sunday, April 7, at 5 p.m. Pacific Time.

A post detailing the thrill of victory and the agony of defeat will be posted Monday, April 8. The grand prize winner will be receiving a trophy, which they can proudly display and use to lord over every other public radio show until next year. That trophy? The Golden Radio.

So what are you waiting for? VOTE! (Click here to view a larger version of the brackets.)