Bruno Mars’ “When I Was Your Man” is aiming for the No. 1 slot on the Billboard Hot 100 chart next week, thanks to continued growth in airplay, streaming and a new discounted price in the iTunes Store.

Mars’ piano ballad has been steadily gaining in chart points for the past 11 weeks. This week, it jumps to a new high, rising 4-2 on the list. It’s currently spending a second week atop the Hot 100 Airplay chart as the most-heard song on U.S. radio, while holding at No. 4 on the Hot Digital Songs sales chart.

Standing in Mars’ way for now is Macklemore & Ryan Lewis’ current Hot 100 No. 1, “Thrift Shop,” featuring Wanz. The cut has been No. 1 for six nonconsecutive weeks.

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Likely working in Mars’ favor for next week is a discounted price for “Man” in the iTunes Store, where it’s on sale for 69 cents. Currently ranked at No. 1 at the retailer, it’s the only song among the top 30 (at the present) priced below the standard $1.29. Industry sources forecast that “Man” could sell upwards of 340,000 downloads by the end of the tracking week on Sunday, April 7 (up from the 235,000 it sold last week, according to Nielsen SoundScan). “Shop,” meanwhile, is trending at about 240,000 for the week, off from the 283,000 it shifted last week, according to SoundScan, placing it at No. 2 on Hot Digital Songs this week.

The sale price seems to be a play for No. 1 by Mars’ label, Atlantic Records, which scored a chart-topper with his previous hit, “Locked Out of Heaven.” The company Tweeted missives to its followers on both April 2 and 3 urging fans to purchase the 69-cent song. Mars himself retweeted one of those Tweets to his 15.9 million followers. (He has the 19th-most-followed account on Twitter.) The song is also selling for 69 cents in the Amazon MP3 store, where discounted hit songs are more common.

Also aiding Mars’ promotion this week is a performance of “Man” on “The Ellen DeGeneres Show” (April 3). His well-received appearance as host and musical guest on NBC’s “Saturday Night Live,” which originally aired on Oct. 20, 2012, repeats tomorrow night (April 6), likely further increasing digital sales for “Man.” He didn’t, however, perform the song on the episode (singing “Heaven” and fellow ballad “Young Girls” instead).

Still, sales is just one-third of the Hot 100’s equation, with airplay and streaming also factoring into the chart’s formula. It’s too early to accurately predict airplay and streaming projections for next week’s finalized charts, but, given the fairly steady nature of the components, this week’s totals offer a rough guide in the potential Mars vs. Macklemore & Lewis showdown.

This week, “Man” holds at No. 1 for a second week on Hot 100 Airplay with 142 million all-format audience impressions, up 8%, according to Nielsen BDS. It’s 38 million impressions ahead of the No. 3 Hot 100 Airplay title, “Shop,” down 7% after wrapping a two-week reign on the ranking three weeks ago. Two days into the new radio tracking week (which runs on a Wednesday to Tuesday cycle), “Man” is up 5% compared to the first two days of its airplay last week. The older “Shop” continues to slide, down 8% over its first two days last week.

On the current Streaming Songs chart, “Shop,” conversely, has the upper hand, ranking at No. 2 with a 6% gain to 9.9 million streams, according to BDS. “Man” rises 6-5 on Streaming Songs, up less than 1% to 4.6 million.

How do these sales, airplay and streaming projections factor into next week’s Hot 100? With next week’s full streaming totals for the two tracks yet to be determined more concretely, projected sales and airplay are pointing toward a slight lead for Mars when the Hot 100 is revealed on Wednesday (April 10). Of course, with three days of sales and airplay still to be tracked and streaming data far from complete, it’s too early to coronate Mars just yet.

Back to Mars’ 69-cent promotion, the strategy brings to mind Katy Perry’s “The One That Got Away,” which was temporarily discounted to 69 cents in an apparent bid for No. 1 on the Hot 100 back in December 2011. Chart-watchers were buzzing after Perry logged her record-tying fifth No. 1 from her Teenage Dream album with “Last Friday Night (T.G.I.F.)” in August 2011. She became the first woman, and second act ever, to tally five No. 1 singles from one album; only Michael Jackson, with five No. 1s from Bad (1987-88), had previously achieved the feat.

So, when “Away,” the next (and final) single from Dream, was released, eyes were focused on the cut, eager to see if it would be the album’s record-breaking sixth No. 1. The sale pricing tactic didn’t work, however, as it ultimately peaked at No. 3 on the Hot 100.

While the top of next week’s Hot 100 will be action-packed with Mars and Macklemore & Lewis (and more), the chart will welcome some exciting new entries, as well.

Jonas Brothers’ first new song in almost three years, “Pom Poms,” should give the sibling pop trio its 17th Hot 100 hit next week. The independently-released track is the first for the act after departing Hollywood Records last May. The group released four studio albums on the label, in addition to EPs, live sets and soundtracks. “Pom Poms,” like Mars’ single, is also sale-priced, but the discount is less steep: it’s priced at 99 cents, not 69 cents.

Elsewhere on the Hot 100 next week, watch for Chris Brown’s new “Fine China” to arrive. It’s the lead single from his forthcoming studio album, X, expected in late August/early September. [Billboard.biz]