Britney's "Circus" On Track 2 Debut At #1

Britney Spears' sixth studio album, "Circus," is on track to debut at No. 1 on The Billboard 200 next week.

Unweighted first-day sales of "Circus" through the close of business yesterday stood at 219,000. Billboard estimates the eight merchants who report to Nielsen SoundScan's Building chart -- Trans World Entertainment, Best Buy, Circuit City, iTunes, Starbucks, Borders, Target and Anderson Merchandisers -- comprise about 80% of all U.S. album sales.

Sources close to the project suggest that "Circus" could move as much as 450,000 in its first week.

If "Circus" arrives atop the tally, it will be Spears' fifth No. 1 album. Among female artists, only four have racked up more chart-toppers: Barbra Streisand (eight), Madonna (seven) and Mariah Carey and Janet Jackson (both with six).

Spears' last release, 2007's "Blackout," bowed at No. 2 with 290,000 behind the debut of Eagles' "Long Road Out of Eden" (711,000).