Player of the Week: Sen. Orrin Hatch (R-Utah)

Sen. Orrin HatchOrrin HatchLive coverage: Senate GOP unveils its ObamaCare repeal bill Grassley doesn't see how Judiciary 'can avoid' obstruction probe Ryan calls for tax reform to be permanent MORE (R-Utah) is facing a defining week of his 36-year career in the upper chamber.

Tea Party activists zeroed in on Hatch after their 2010 defeat of then-Sen. Bob Bennett (R-Utah), whom they claimed was not conservative enough. The same activists see Hatch as a Washington insider, and hope to seal his fate at Thursday’s Republican caucuses. 

As The Hill’s Cameron Joseph recently reported, the caucuses select delegates to the state convention, where the party determines whether to conduct a primary for Hatch’s seat.

The key for Hatch this week is to ensure that 60 percent of the convention delegates support the senator. That way, he’ll avoid a primary. Conversely, if anti-Hatch efforts topple 60 percent, the Utah senator will not serve a seventh term.

Hatch has run a far better campaign than Bennett. That was evident last summer when Rep. Jason ChaffetzJason ChaffetzThe Hill's 12:30 Report Chaffetz: Trump administration 'almost worse' than Obama's on transparency Utah GOP narrows field for Chaffetz seat MORE (R-Utah), who had long been eyeing a challenge to Hatch, opted out of launching a bid against the six-term senator.

However, other GOP candidates have announced their intention to take Hatch’s seat. And the Tea-Party affiliated FreedomWorks has made it a top priority to defeat Hatch this cycle.

The group has acknowledged that Hatch is a tougher out than Bennett as the Utah senator has taken the lead on a range of issues favored by the right, including a balanced-budget amendment and the eradication of the 2010 healthcare reform law. (Hatch is no Johnny-come-lately to a balanced-budget measure, which he nearly pushed to passage in 1997.)

Hatch for months had argued that if he loses in a primary, centrist Sen. Olympia Snowe (R-Maine) would be in line to be the next chairwoman/ranking member of the powerful Finance Committee. Snowe’s stunning announcement last month of her retirement strips Hatch of that talking point. 

Hatch has lined up some key backers, including White House hopeful Mitt Romney, Fox News conservative commentator Sean Hannity and right-wing radio talk-show host Mark Levin.

If Hatch survives, other incumbent lawmakers might follow his playbook. If he loses, it will highlight the danger to anyone running on a decades-long career in Washington.