The Late Shift Shifts to Jon Stewart in Key Demographic.

Since 2000, NBC's Tonight Show and host Jay Leno have consistently topped the ratings every quarter. (That's 40 quarters in a row — just saying.)

And while still beating out the competition in overall viewership, focusing on the all-important 18 to 49 age demographic shows The Daily Show With Jon Stewart narrowly pushing into the lead.

(In fairness, Stewart had just 3,000 more viewers in that bracket than Leno.) Still, this likely marks the end of a ten-year streak for The Tonight Show, which will struggle to regain top spot as we enter presidential campaign season, when Stewart and former protégé Stephen Colbert are at their satirical best. And let's not forget that now Colbert has all that Viacom money at his back, thanks to his recently approved Super PAC — actually called "Americans for a Better Tomorrow, Tomorrow." Sorry, Jay.

Top 10 Late-night Talkshows (Adult 18-49)

1. The Daily Show with Jon Stewart (1,295,000 avg viewers)

2. The Tonight Show with Jay Leno (1,292,000)

3. The Late Show with David Letterman (1,096,000)

4. The Colbert Report (960,000)

5. Late Night with Jimmy Fallon (842,000)

6. Jimmy Kimmel Live (766,000)

7. Conan (748,000)

8. Chelsea Lately (720,000)

9. The Late Late Show with Craig Ferguson (702,000)

10. Lopez Tonight (340,000)