As Alaskans vote on Joe Miller's unlikely primary challenge to Sen. Lisa Murkowski today, the election will prove yet another test for the Tea Party movement and, more importantly, its ability to channel money to races around the country.

Tea Party Express, the only national Tea Party group to endorse candidates and spend money on races, has emerged this election cycle as a major conduit for Tea Party campaign money, and it has poured hundreds of thousands of dollars into Alaska to back Miller.

Since endorsing Miller June 16, it has spent over $560,000 on TV, radio, and direct mail on his behalf.

As Alaska pollster Ivan Moore told The Hill, the Tea Party isn't very strong in Alaska, numbers-wise. If Miller has a strong showing, it will be thanks to the money Tea Party Express has brought in from outside the state.

Tea Party Express has made its mark on this election cycle, with one major achievement under its belt: the group is largely responsible for Sharron Angle's presence on the ballot in Nevada, having endorsed her when she polled at five percent in her multi-way primary. Some low-budget TV ads and more than $400,000 in spending later, Tea Party Express had catapulted her to primary victory.

That was not the beginning, or the end, or Tea Party Express's spending prowess. The group spent just under $375,000 in support of Scott Brown, $115,000 on New York's 20th district special election in the spring of 2009 (which Democrat Scott Murphy won), and $65,000 to chase Democratic Congressman Bart Stupak into retirement after he acquiesced to the White House's abortion compromise and voted for health care reform.

In Alaska, it backed Miller in conjunction with Sarah Palin, who issued her endorsement a week and a half earlier. Palin has spoken at Tea Party Express rallies, sans speaking fee, and seems to enjoy a close relationship with the group.

But Palin hasn't done much for Miller. She recorded a robocall, and Todd Palin held a fundraiser for him, but almost all of the help Miller has gotten has come from the influx of independent spending from Tea Party Express.

As of the last financial filings on August 4, Miller had spend just under $200,000, Murkowski had spent $2.1 million, and Tea Party Express had spent $115,000. Given Miller's vast cash disadvantage, a strong showing will be a credit to that group.

And a strong showing is almost all Miller and Tea Party Express can hope for. With Murkowski established as a popular incumbent before the race, and after only two months of spending on Miller's behalf, Tea Party Express spokesman Levi Russell acknowledged yesterday that it would be a big upset if Miller were to win, but that the group hopes Alaska will be another opportunity to flex some "Tea Party muscle."

Having succeeded in the cases of Brown, Angle, and Stupak, but failed in New York's special election, Miller's showing will serve as one more metric of the Tea Party movement's financial prowess in 2010.

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