Since 2005, there has been much speculation on whether Sen. Lindsey Graham (R-S.C.) would face a formidable challenger in the 2008 GOP primary.

That chatter was triggered by opposition from the right to a Graham-backed comprehensive immigration bill and to the senator’s role in the “Gang of 14” that struck a deal on judicial nominees three years ago.

The senator’s campaign website seeks to balance independence and conservatism. It states: “Graham is known as a leader who never abandons his independence or strays from the conservative reform agenda.”

But despite all the talk, Graham faces only nominal opposition in next week’s primary. Even his opponent, retired orthodontist Buddy Witherspoon, likened his race with the 52-year-old senator to “David and Goliath.”

Not surprisingly, Graham recently said that he’s not worried about Witherspoon.

Hometown newspapers are praising Graham. The Greenville News wrote that Graham is the clear choice for the GOP nomination, adding he has “served this state well in his first term.”

The paper added, “Witherspoon has questioned Graham’s conservative credentials, particularly on immigration, but the fact remains that Graham has been a strong conservative voice for this state. Graham has been an outspoken supporter of lower taxes, less spending, strong national defense, less regulation, conservative judges and reining in entitlements.”

And while Senate Democrats are targeting many Republicans this cycle, Graham is not one of them. After winning easily next week, Graham is expected to cruise in November to his second term.

Several years ago, Graham took a lot of shots from the right. Today, he is a leading GOP voice and Sen. John McCain’s (R-Ariz.) point man in the upper chamber. He has shown that he will not hesitate to criticize Sen. Barack Obama (D-Ill.), and the Graham-Obama relationship is one that will surely get testy in the next five months.

Graham has downplayed the chances that McCain will put him on the presidential ticket. But unlike other possible veeps, Graham honestly believes he is better suited to help McCain in the Senate. He makes a good point.

He is well-versed on a range of issues, serving on five committees: Agriculture, Nutrition and Forestry; Armed Services; Budget; Judiciary; and Veterans’ Affairs.

Graham is young by Senate standards and after showing he can take a punch, it is likely that he will be on Capitol Hill for a long time.