Before April 15, Sharron Angle wasn't even on the radar. Nevada's crowded Republican Senate primary, which will determine Senate Majority Leader Harry Reid's challenger in the fall, was looking like a two-way race between Sue Lowden (a former state Senator and Nevada GOP) and Danny Tarkanian (a real estate businessman and former lawyer who played point guard for his father at UNLV).

Then Angle, a former state assemblywoman, earned an endorsement from Tea Party Express, the group that puts on high-profile Tea Party bus tours. After that, things changed.

Since that endorsement, Angle has gained 20 percentage points in polls, shooting ahead of Tarkanian and becoming a viable contender to win the race.

In an April 5-7 Mason Dixon poll, Lowden led the race at 45%; Tarkanian ranked second with 27%; Angle, meanwhile, collected only 5%.

In the most recent poll, however, Angle has leapfrogged Tarkanian and trails Lowden by only 5 percentage points. Lowden leads at 30%, Angle places second at 25%, and Tarkanian ranks third with 22% in the May 10-11 Mason-Dixon poll.

15% of Republicans surveyed don't recognize Angle, which is about 10 points worse than Lowden and Tarkanian, but it's not bad for a candidate who was considered inconsequential only a month ago.

Angle can thank Tea Party Express for a $300,000 TV and radio campaign. The group is purchasing another round of air time, worth another $100,000, and it has launched a direct-mail campaign on Angle's behalf.

The group has been soliciting donations to help Angle win. Spokesman Levi Russell says the money is being put directly toward independent expenditures in Nevada. (TPE is an arm of the Our Country Deserves Better PAC, which was launched by Republican consulting firm Russo Marsh + Rogers. Donations technically go to the PAC, as it's the PAC that files with the Federal Election Commission.)

Other prominent Tea Party groups don't endorse candidates, which means TPE's endorsement has made Angle the only candidate in this race who's tied, in an official capacity, to the unofficial "Tea Party" brand. Apparently it's helped.