President Barack Obama has used Twitter to fight political battles before -- he tweet-spammed over the summer as the deadline for raising the country's debt ceiling closed in.

Today his staff is encouraging people to use the hashtag #40dollars and tweet what $40 a paycheck means to them, the amount the average American stands to lose if Congress does not renew the current payroll tax cut by Jan. 1, 2012. By late this afternoon, #40dollars became a trending topic on Twitter.

House Speaker John Boehner is using #payroll in his tweets about renewing the tax cut -- but that term is most definitely not trending.

[ Those not on Twitter can leave a message (and a photo if they choose) at http://www.whitehouse.gov/40dollars but must also give their email address. ]

Macon Phillips, the White House Director of New Media, tweeted at 4pm PT, "Messages coming into wh.gov/40dollars at around 2000/hour #40dollars #gulp."

It's not yet clear if the campaign will work. NBC News White House Producer Shawna Thomas tweeted, "The White House's new tactic on the pay roll tax cut: Asking the twitters what $40 can buy. Interesting to watch the #40dollars feed."

The problem with the #40dollar stream -- at least until about 4:12pm PT -- was that about half the tweets were spam for some version mortgage or forclosure help, making it harder to find seemingly more legitimate messages about using $40 for things like medication and health insurance, utility bills, gas to get to work or school, kids' lunches and family groceries, and student loan payments.

We also noticed that in tweetdeck (not on Twitter.com), you see a promoted tweet for a tie sale.

LAUNCH asked Phillips how many of the tweets coming in were spam, to which he tweeted back, "was talking about what's coming in via the wh.gov website - but a lot of the tweets using #40dollars are terrific."

Although the mortgage spam appears to have stopped, we're seeing snarky messages like "#AlliWant is #40dollars" and "#40dollars can get you somewhat alot of weed lol."

LAUNCH Blog